Not particularly, and it wasn't intended. We sunk it on dry land.
See, there were these huge vacant lots behind my house. One summer, my friends and I spent a lot of time there having dirtclod fights - basically just fliging stuff at each other.
That got boring, so we started digging trenches to supplement the dirtpiles that comprised our "forts". Eventually, we had 200-300 or so feet of trench dug.
Then we thought it'd be cool to make tunnels. The bottom half of the tunnel system was already there, in the form of the trenches.
So we went out and scrounged wood scraps from construction sites - plywood, 2x4s, 2x6s and whatever we could find. We put the boards across the trenches, laid the plywood on top, and covered with dirt. Voila - tunnels!
We also built an underground "meeting room" by digging out about a 10-ft diameter hole about 4-5 feet deep. We roofed it like the other tunnels, which connected to it for secret-meeting access.
It was a fun summer: building, meeting, plotting against the girls.
But that fall, somebody bought the lots and a couple months later started clearing it for construction. After the summer rains, weeds and grass had pretty much obscured our tunnel network, which was cool.
But the guy driving the bulldozer also didn't realize the underground network existed. We were watching over a wall when he finally drove over the wide, deep meeting room and caved it in.
Bulldozer went down nose-first into the meeting room - sunk about halfway up the treads, ass pointing to the sky.
Scared the hell out of us, nobody hurt, but it took a couple days to get the dozer out. Dozer driver was pissed, but we never fessed up; too scared.
Having fun can be a lot of work.
The father said: "Thirteen years old and you've already caused a three car accident....and you don't even have a driver's license."
In the meantime......The 3 year old granddaughter (daughter of a cop) was caught "laundering money". Yes, mommy had told her that money was dirty. She laid out the freshly "laundered" bills on a towel in the bathroom. Mommy dutifully reported the incident to Daddy, the "cop".