I've been thinking about what to build for my "mini-table" again, I want it to be around 60cm x 60cm.
I've had loads of ideas, the Desert Island "Spit of Land" being the most appealing to me personally so far (as discussed in this previous post).
Another thought that appeals is the idea of a Treasure Cavern like seen at the end of Pirates of the Caribbean "Curse of the Black Pearl" - complete with Treasure Piles, Rock Pools, and a surrounding backdrop for the cavern walls!
Of course, if space was no object - I would simply HAVE to have a shipwreck in there too!
