Just a passing thought. I’ve never seen a picture of a sub showing one. (We’re talking about boats here, not sandwiches) 
Of course they do.
Yep. I’ve been anchored in Lahaina harbor off Maui on two different submarines.
They are faired into the hull on modern nuclear subs, since otherwise they’d cause turbulence, and therefore noise, when the submarine is travelling submerged (i.e. all the time). So it’s not obvious looking at the hull, like a surface ship or one of those prehistoric subs that silenus linked to.
Thanks, all. I kinda sorta figured they had anchors, but I could never see one. (Not that I looked very hard) 
It’s located just aft of the screen door.
There’s some thought that the CSS Hunley had an anchor. An anchor was found that was perfectly in line with the sub, and it some think that maybe the plan was to anchor out in the water until favorable tides would allow them to sail back in more easily.
Anchored out off St Croix, Lahaina and Pattaya on my first boat, and Cartagena on my third.
As noted above, it’s under the boat (or at least it is on a 688), and it’s faired into the hull to prevent turbulence.
During wartime (WW2 anyway) they were often removed and left ashore, as there was little need for them, since the sub wouldn’t put into port except at a dedicated sub base where it could tie up alongside. It was difficult to prevent the anchor chain from shifting and making noise, making the sub easier to detect, and there was also a risk that the shock of depth charges might break the anchor free and let it run out. Aside from the danger of fouling the dangling anchor in shallow water, this would create a *very *loud noise.
Oddly enough, subs do have a screen door. Actually it is an expanded metal hatch insert. Good for ventilation and keeping random thrown items out of the sub.
OK fine. The USS Nautilus has a house type screen door on the hatch an dladder area they made for tourists, so they don’t have to climb down a weapons shipping hatch to get into the sub. [I always hated the vertical ladders going into the Miami and San Juan. I always felt that I was going to fall on someone. If I could have teleported down to Machinery 1 I would have been happy. That was my favorite place to hide out during dependents cruises anyway.]
I may have posted this before.
During a maneuvering watch outbound from Holy Loch the man at the anchor station managed to inadvertently release the anchor which, since the ship was in motion, reached the end of its chain which parted leaving the anchor and chain behind.
So for months until it was replaced the following qual question was valid.
Q: Where is the ship’s anchor located?
A: Firth of Clyde!
So you were in the sub fleet prior to 1991?
Yes, on the Batfish out of Charleston from 1984-88. Are you implying I’m old?
Nope, probably the same age we are He joined up in 1983 and was in Great Mistakes for the January class. Being a desert rat from California he was not thrilled:smack:
January 1983, I was finishing sub school and headed to San Diego.
Photo of an anchor on the USS Henry Clay in drydock. The bottom of the anchor is the “bow tie” on the right.
(How does the crew guarantee that the anchor is weighed without the chain twisting, to ensure that it fits into its niche? I am sure that the winching mechanism forces the chain into a prescribed path, but I have never seen an anchor that was immune to currents.)