I liked justuspr's DND Longboat, but I wanted to be able to make a few different types and thought I'd make my own. This is my first stab at making a boat in Solidworks. I used the basic size of justuspr's model for reference. I may revise this or add another version as I continue tinkering with it. It's slightly wider, but the interior flat of the boat is a little smaller because of the revolve I made for the walls.
The hole is sized to work with the mast for justuspr's DND Longboat:
EDIT: Added version 2. Slight modification to make the bottom flat surface a little bigger.