Cavern Basic Set D

Publisher's blurb: The Cavern Basic group of Naked Geomorphs contains 15 tiles, each with one multi-position opening (CD, CSD, CSSD, etc.) and the remaining positions filled with rock (R). Sets A, B, C and D are completely interchangeable. I.e., tile C1A can be replaced with tile C1B, tile C1C or tile C1D, without changing the basic structure of your map.