This is for the Steam version of Sven-coop (which is free)
Its a big underground aquarium and a partially underground house attached to it. The aquarium is mostly complete, as well as the terrain which the house is dug into, but the house itself is very incomplete.
I'm uploading the .bsp so that you can load it up and have a look around, and the .rmf so that you can open it up in Hammer and finish it, in what ever way you like. Maybe get creative on the house or turn the map into a deathmatch map or a single player map, whatevs
The only reason this is for Steam Sven-coop is because I made use of some of Sven-coop's textures but you just as easily load this up into Hammer configured for vanilla Half-Life and fill in the missing textures.