tutorial (third post), it refers to overland mapping but maybe you can pick up some techniques and adapt them for your purpose in the end it is all about the textures you have.
If you decide to work with textures you could use an alternate version of the mountain techniques used by pasis to 'bank up' some earth piles around your construction side.
Great to see you working on this! Imho the lables, how simple the might be, add a lot already
If you can't find suitable textures, let me now and I'll browse my archive for you.