This is pretty obviously a map exploit but some people say it isn't so I'd like a definite answer.
So on the map ba_jailfort_b1 you can reach the boat area by having two medics usually with the quick fix exiting from that random exit next to trivia and looping around the race track to the pier. Normally you would have to hit all the black panels (which you shouldn't be able to do since one is in a blue side area)
If you don't know what is the boat area/pier here is an image of the place and a demo showing the path to get there
Not just a way for me to prove a point
If you don't know what is the boat area/pier here is an image of the place and a demo showing the path to get there