Sure seems that way inside. It's got a slightly larger vertical profile than a 55 gallon drum, so imagine you and seven of your closest friends doing heavy physical labor with no fresh air inside of a row of 55 gallon drums that are standing upright next to one another.
http://www.hunley.org/ You can only look down into a pool of water where they keep the actual Hunley. You can clearly see it, but you cannot actually touch the real one. You get a very good view though.
