The Offshore Voyaging Reference Site

ShoreFasts—Part 1, When to Use Them

Over the years, members have asked me to do an article on securing a boat with shorefasts as a replacement for, or adjunct to (more common), anchoring. So here we go.

But before we get into what gear we need and how it’s done, let’s look at when we should use shorefasts and, more importantly, when we should not.

The answer is not often, and only when there is no other choice.

I know, that came as a surprise since I’m sure most of you thought that a sailor with my some 25 years in the high latitudes would be lacing his boat into a snug cove at every opportunity. 

Nope. In fact, I will go a step further and say that using shorefasts is often poor seamanship and sometimes downright dangerous, and it’s almost always a last resort.

Why? Simple physics coupled with common sense. Let’s take a look:

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Dick Stevenson

Hi John,
I felt the math was beyond me, but agree experientially on all points.
In Turkey and Greece there were a lot of shorelines that rapidly became too deep for free anchoring necessitating the boat being stern-to the shore (a tree or rock usually). Even moderate wind from abeam had forces that were quite unsettling and I never got used to not swinging to the wind.
And it is my estimation that shorefasts in higher lats (may) demand, to execute easily and safely, a crew greater than husband and wife as well as a good dinghy with a decent dependable engine. When we sailed to Greenland, one of my major concerns, that I fretted about a good deal, was accomplishing shorefasts safely. One change we made from our usual cruising, just Ginger and I, was to have another experienced and athletic crew, in large part to address that problem.
My best, Dick Stevenson, s/v Alchemy

Matt Marsh

People often don’t realize just how streamlined a sailboat is head-on, and how much resistance it presents side-on.

We specifically design them that way. Enormous resistance to any side-to-side movement is a key part of how we make sailboats capable of going upwind. Extremely low resistance to fore-aft movement is a key part of how we make them capable of moving under sail at all. They’re designed around the flow of water past the hull while the boat’s in motion, but the flow of air over the topsides and the crashing of waves along the waterline of a stationary hull must necessarily follow similar laws.

In short, a boat perfectly side-on to wind & waves presents about three to four times more exposed area, with at least twice (possibly three times) as much drag per unit area, than a boat perfectly head-on to the same stuff. And when things snatch up tight, there’s a shock loading factor on that too. So yeah…. beam-on forces being on the order of 6 to 12 times the head-on forces in similar conditions is probably about right. That’s just the force on the boat, without considering the reaction loads on the anchor rode or shorefasts!

Now let’s allow for some yawing at anchor, call it a doubling of load at max yaw. But shorefasts tend to snatch up tight, which brings a large and very hard-to-determine multiplier into play. I’d guess that a boat on shorefasts seeing 10x to 15x the wind & wave force of a free-swinging boat on an anchor rode & snubber is probably about right.

But wait! That’s just the forces at the boat. We haven’t applied the geometric multiplier yet.
So 750 pounds of pull on the anchor in a good blow…. corresponds to 7500 to 11,000 pounds of pull on a perpendicular shorefast…. or up to 26,400 pounds on a shorefast at 12°… now what will 3/4″ Dacron braid do under that, I wonder….

Oh, but what happens *long* before the ropes break, in the scenario John sketched above? Right. The anchor drags, the tree roots rip out, and you’re up on the rocks.

That’s all very back-of-the-envelope. Some day, when I’m bored and have time, I should drop a 56-footer into a CFD model beam-on to a 60-knot blow and matching waves…. then show the result to John just to scare the jeepers out of him.

Drew Frye

This is just begging for load cell work!

Something I observed when measuring dock line loads is that gust on the beam (no waves–we are talking protected marina settings) don’t generate as much force as gusts on the quarter. As you pointed out, a gust on the bow or stern are relatively streamlined. Gusts on the quarter meet more resistance and get the boat moving, generating momentum. But gusts on the beam are partially counteracted by the keel, which reduces the momentum gain, although not the static force.

The math is really complicated in practice. I’ve always disliked bow-stern anchoring. I’ve only done shore ties twice. Each time I set a big anchor well at huge scope, and no matter how it was power set, it still moved a little. I had to retension whichever lines became slack to control the motion, and it was good that I had allowed enough room for that. Retensioning the loaded side will be impossible.

Stein Varjord

I think the following belongs with the next article, so just shortly (for me…) here, related to angles… When I use a shorefast, there are several steps, but some are:
– I take the bow to land where we want to be, to check it’s suitable.
– I go out again, spend some time considering exactly where to drop the anchor to get plenty of scope and correct pull angle.
– Then I go back in to the shore, set a single shorefast and decide the anchor tension that makes it just possible to jump ashore from the bow, but the boat can’t hit anything.
– Then I add at least one shorefast, normally two. The shorefasts are angled as far apart as possible so that they don’t pull the boat inwards much, just controls the sideways position. Sometimes I also bring a long angled shorefast to the stern, to keep the boat more aligned without pulling too hard on the anchor. This can make a huge difference, but not completely remove the problem of extra anchor load.
– One shorefast is put straight towards where we want to jump off/on. This is used to pull the boat in. When not pulled, the boat goes out quite a bit. That way the whole system can be kept rather loose and the angles stay healthy. When going on and off the boat frequently, this line is tied short enough to step on and off without pulling. At night it’s let out.

This method makes “Scandinavian moor” very nice to use in suitable locations and conditions, and reduces some of the inherent problems, but it won’t remove the problems. Shorefasts do always add complications and risks we need to monitor. Shorefasts are rarely suitable if the boat is left alone.

Stein Varjord

Hi John,
I’m planning to comment more in detail on the same topic on the next article. What I intended to comment on here was the angle – anchor tension issue, but I didn’t really make that clear… I’ll try to become better at filtering out related thoughts that are not constructive at the moment. My mind is mostly working via association, so self sensors hip is needed.

Marc Dacey

Reading Novak and high-latitude authors such as Hal Roth, among others, one would assume taking a loop of 200 feet of stout line around a boulder was practically mandatory. Thanks for countering that position with logic and experience. I look forward to the follow-up, as I do have a stern anchor at the ready, but we’ve never resorted to it, and there’s a bit of overlap in the concepts, I would think.

Kristoffer Naes

Hi John,
Living in southern Norway I used to anchor the Scandinavian shore fast way. However, I often found myself in trouble at night when wind shifted. Not pleasant being worried and having to go out of bed to adjust. My solution: Bought a Spade one size up and an anchor sail as you pointed out earlier. Quiet nights after that. And with children that want to go ashore: They use the dingy and learn to row in early age.

Stein Varjord

Hi John,
Another Scandinavian here, who has cruised most of Scandinavia and much more, and use shorefasts almost always in those areas. That indicates that I disagree with your observations, but I don’t. I agree with it all and can confirm that Scandinavia is indeed mostly very easy cruising grounds (if we know how to navigate with 100% precision…)

The reason I like using shore fasts isn’t safety but comfort and feel. I cruise to experience the locations I go to. I like to be as close as possible to what I’m visiting. I love being able to step ashore on a cliff from the bow. (In case someone doesn’t know, “Scandinavian moor” is bow in, while “Mediterranean moor” is stern in). Mooring like that is certainly not safer than anchoring, but it’s normally worth the extra attention, if the weather and location is suitable. In the Scandinavian summer, both are usually very much so.

There’s also another reason for this type of mooring in some parts of Scandinavia, especially the most popular southern coasts: In the small coves its shallow and the bottom is normally sand or mud, suited for an anchor, while in more open water, it’s often very deep, the bottom might be smooth bedrock and often far from flat. The multitude of small islands makes it easy to find coves everywhere.

Trevor Robertson

Hi John
Another reason to avoid using shorefast lines that applies to a berth pestered by ice is that the lines collect ice as the wind picks up. Some of this ice snags on the lines; some of it bumps its way to the downwind end of the shorefast.

The ice snagged on the lines may weigh several hundred tonnes. The strains on the shorefast lines are frightening enough when a strong cross wind is blowing on the boat without the added strain of using the lines to corral all the stray ice in the bay then trying to hold this ice in place.

As the wind is almost always oblique to the shorefast line’s direction some ice bumps its way downwind along the line and concentrates at leeward end of the line, either at the vessel or against the shore. The objection to using the shorefast to direct many tonnes of jostling ice against the hull in strong winds is obvious. If the ice is driven to the shore end of the line it may get under it and, as the tide rises, lift the shorefast from the boulder to which it is tied. I once came close to losing Iron Bark this way. It is not always possible to find a boulder high enough above sea level to avoid this. In my experience attempts to use halyards to lift the shorefast lines above drift ice generally fail.

As you say, if there is room and adequate holding, laying to anchor is preferable on numerous grounds, but unfortunately not always possible.

Dick Stevenson

Hi Trevor and all,
You remind me: we were with another vessel on the E side of Greenland waiting for Prince Christian Sund to open. They were spider webbed in to a cozy space with a number of shore-lines. We free anchored deep. They were clearly safer if a blow had come through, but they were regularly harassed (and worried by) by moving ice which got hung up in their lines. We also had ice that wanted to mate with Alchemy, but that slid by easily and went its way.
My best, Dick Stevenson, s/v Alchemy

James Ferguson

Just a couple of notes. I kept my CQR around for a few years in our high latitude sailing in case I needed it to wedge it behind a couple of huge boulders in Newfoundland, Labrador, and Norway. Also when we were in Alaska a man was killed by a surprised grizzly while tying to a tree. Just another sad experience to consider.

Thanks for another great read.

Lee Youngblood

Hi John,

Just a question, if you tied your stern-tie/shorefasts lines to your anchor chain and let out a little more chain, would that allow you to pivot/swing around from a single point and not get caught beam-on to the wind loading up your gear?
I know you hate more complications, but maybe you could use a small dynema soft shackle or scrap that you could quickly cutaway, when you needed to leave in a hurry?
2 cents – I’ve been pushed sideways, while stern tied in a crowded BC harbor, and it didn’t feel good. . . Thanks

Matt Marsh

That looks relatively good from a loads standpoint….
but if the wind shifts, now you have the boat’s hullside lying against either a rode or a shorefast, which will be forced under the hull and tangled around the keel / prop / rudder.

P D Squire

Drop the junction where the 3 lines meet by attaching a few meters of chain between the junction and the bow. As the boat swings the line ahead will become taught and the line you’re trying to run over will be slack and sink further. Sail a centre board boat with a solid member joining the keel and rudder below the prop.

Eric Klem

Hi John,

It is somewhat relieving to hear your view on shorefasts, in my somewhat limited experience I have come largely to the same conclusion.  In the PNW, I have used them to deal with very steeply sloping shorelines where you might drop in 60′ of water with the anchor only 150′ from shore.  I have also used them a handful of times in both the PNW and US northeast to fit into a truly tiny spot.  But all of this is super settled weather only type use.  While I have never dragged an anchor significantly doing it, I have been forced to pay out a lot of shorefast line to change the loading negating a lot of the reason for it in the first place as the boat is now where it wasn’t intended to be.  I can think of at least 1 anchorage where we used to use a shorefast because there wasn’t swing room but since switching to our Mantus anchor which works much better at short scope, we can now swing free in the same spot.

I have also witnessed more than a few interesting situations resulting from the use of shorefasts, thankfully not being directly involved in any.  I can think of at least a few groundings while getting set up (none bad) and several issues with the person ashore including loss of the dinghy, slipping on seaweed, etc.  I am sure that there are even more ways to get in trouble if basic seamanship isn’t practiced such as getting a line in the prop but I can’t remember ever witnessing that.

I am not sure that I am understanding your comment about angles over 30 degrees not being beneficial.  30 degrees is special because at 30 degrees, the component of the force that is in line with the wind force is half as big and since you have 2 of these components, now the anchors each see the same as the wind force.  If you go really extreme and go to 90 degrees, the component is now equal and you end up with each anchor only having half the wind force.  Of course, this is a silly example as the rodes are now parallel and you loose all the benefit of a shorefast.  30 degrees does seem like a good number to shoot for but more can be beneficial too but it seems like an unlikely situation with a single shorefast.

Cruising on my uncle’s boat in the PNW, we carried a small amount of special gear for this but on our own boat, we don’t carry any special gear for it and have never had that be an issue.


Eric Klem

Hi John,

Understood on the 30 degree comment.  From a practical standpoint with a single shorefast, that is probably the limit anyways.

In some places (PNW is where I have seen this), there is unfortunately no lack of excitement with shore-ties due to the number of people doing it.  I find myself sort of compelled to watch, probably because I have witnessed it go badly enough times.


Marvin Hamm

I was curious where you were going to head with the reasoning against this kind of anchoring. As soon as I saw your side load graphic it all made sense, I didn’t even have to read further. I while ago I was wondering what the tension loads were on the hammock that I had set up in the back yard. I don’t recall the exact number, but was more than a little surprised that sitting 160lbs down on the hammock was creating tension loads way above 1000lbs. I had never applied that idea to two-line anchoring before. What is going on is obvious now. I just hadn’t put the two ideas together, visualizing my boat as the hammock under tension.

Rob Gill

Hi John,
“Morgan’s Cloud hiding from ice by using shore-fasts”… We may need them if we ever get to Patagonia and if so, if I get a photo like that one, it will have been worth the effort – beautiful.

Flemming Torp Petersen

Hi John,
I’m one of the sailors from Scandinavia that has been sailing in Norwegian, Danish, Swedish and Finnish archipelago waters most of my life.
With many hundred nights shorefast and/or at anchor.
I learned the hard way … why we should avoid shorefast.
Some years ago – my wife a couple and myself – arrived at a popular place, and placed our boat parallel among several other boats, perpendicular to the shore, the bow moored to the cliff, and 30 m. nylon line and 10 m. chain to the Fortress anchor from the stern …
At around 3 o-clock in the morning, we suddenly noticed that we got very strong unannounced gusts from starboard side. We “ran” to the cockpit in our underwear … to see, what was going on …
Lots of panic and screaming around us. Several boats simply dropped their moorings from the bow backed with the engine, and tried to save their anchor. Several boats gave up on saving their anchor, some boats collided with other boats … Most boats fled from the the popular anchorage.
The pressure on our stern anchor line was so hard, that the two of us were unable to quench the mooring from the clamp.
Luckily, the Fortress did not give in, and with the “neighbour boats gone”, we were able to relax the mooring from the clamp in the bow – and we were sitting in the cockpit the rest of the night … keeping an eye on the situation.
After a few hours the wind reduced, and “we were out of danger” …
But is was a very useful lesson, and we have since avoided to shorefast for the night …
Using our SPADE anchor with chain from the bow, we have since enjoyed many nights, some with pretty rough gusts – and we have slept without worries …

Robert Tigwell


Wow…. you have such great content. And compared to everyone else on this chat I am a junior even though I have spent a lifetime on the water. I have read through section 1 and 2, but came back here to leave my comment as some of it pertains to section 1 content.

Your calculations for load on an anchor with a single shore-tie as:
“At that 12˚angle, loads when a 40-knot gust hits us on the beam will be about 2.4 x 4 x 750 = 7200 pounds (3265 kg). ”
Conservative, and huge still – I agree. But, just a math consideration – wouldn’t this load be the total shared between the anchor and the shore-tie? Thus, load on one or the other would be half. Wouldn’t this apply in all your calculations?
If this where the case, then the load expansion on a 3 point with 30% angles, instead of being a 3.2 multiple would only be a 1.6 multiple of standard anchored load and make me feel a lot better (since I tie that way all the time).

Now for some bare honesty… and to add to your list of (non-seaman-like) reasons why people do a shorefast/bermuda mooring/norwegian mooring and then regret it at 3 AM when the blow comes:

– privacy in busy anchorages – If I pin my stern to shore, I get to enjoy my own little world in my cockpit get privacy away from the view of the 20 other boats in the anchorage.

– recreational safety – kids can swim and the boat isn’t moving around on them. Mom is happier being lifeguard on duty, and the waters are usually a bit more sheltered.

– for the dog (my personal favorite) – the dog can swim ashore to do his business and swim back, helping me be a less responsible pet owner.

– consistency for the less-boat-friendly – some guests finds it uncomfortable when looking out and the view is different because the wind has shifted or we are just yawing about. “are we dragging…..” (very obvious when you are tied in – and unsafe as you mention)

– to stop the yawing in my modern production tuperware boat (Hunter 39) with the mast so far forward it is like a cat rig with an accidental foresail. (I now have an anchor sail to calm the beast and it works, as per your other article on yawing control)

And like our Norwegian contributor (I think in section 2), to get good and close and stay out of the wind’s way. (I now hesitate to consider this a good approach thanks to you !)

As many would share, some of my worst experiences at anchor have been while using a shorefast that was ill-conceived and for less than nautical reasons. Over the years I have refined my harbouring with a simple set of rules. I only bermuda moore with my bow facing into the worst possible direction (most exposed) for wind, and ensure a high level of shelter on each beam. And, most ideally, stern-to in the forecasted direction (on lee shore I should say), so if wind is as predicted, all load will be on the shorefast. Rare I can get all that in, but I am not on an ocean so my ‘worst’ is not usually over 30 knots of wind. (Great Lakes – Georgian Bay)

Looking forward to section 3 and the equipment you use. Although we don’t have tides, sharks, kelp, and frigid water, we do have a LOT of rocks and rope-eating shoreline features. Happy sailing everyone and stay healthy.

Please keep writing — much appreciated.

Greg Bernard

Good article, but then I never needed any convincing. Here in BC, we call the lines run ashore “stern ties”…the practice is exceedingly popular for a number of reasons:
-The anchorage is popular – lies run ashore let’s us stack them in.
-The water is too deep to swing free.
-The anchorage is too tight to swing free.
-Everyone else is doing it.
When is comes to anchoring on this coast, we are blessed. There countless sheltered anchorages with thick mud and reasonable depths. Anchoring is pretty easy here. Furthermore, the winds in the summer are light, especially overnight. I think these favourable conditions let people “get away” with running a line ashore night after night, deluding themselves that they are actually secure when the truth is that they never really needed to be.

My wife and I hate “stern tying” and avoid it whenever possible – which is almost always. In an 80 day cruising season, we’ll run a line ashore 4 or 5 times, almost always because of limited swinging room, and only with a favourable weather forecast. In the more crowded anchorages, we can often swing free in the empty space all the boats snugged up to the shore have left in the middle of the cove. We’ve seen some pretty crazy techniques used to deploy stern lines, some more successful than others. I’ve written a blog post to outline our method, which for us, is just about always stress free and efficient. (BTW, I get no $$$ from my blog – I’m sharing it as service)