When I was writing GSXX, I made a grid for my own curiosity to see how much space would be available on the ship. In my head, I imagine the generation ship being 30 miles long, and so I went down a small math rabbit hole to find out how I could determine the available square footage on the interior of the cylinder.

So! Here's the result of that! It came out to something like 30 miles long by 31.3 miles wide - the map is simplified to 30 x 31 (that pesky extra 1), for a total of 930 square miles of available surface area.

Today I thought I'd upload the grid so that it could be used as a floor plan for your own ships!