This odd-looking tree grows in Chih Shan Park, a site of historical and religious artifacts in the Shihlin District of Taipei, where I live. All of the things you see on the ground are roots from this tree. I don't know what kind of tree this is, but I've never seen anything quite like it. I was told that the tree is probably over 300 years old, although I can't vouch for that.

Canon EOS-3, 28-70 f2.8 L, Kodak Supra 400, 1/60 sec @ f8