The tower near the entrance to Dagnors Cauldron (loc 1538, 842, 4.5)? It looks like it's made of bamboo and skulls.
YES! A slight correction, Finfan, the location is -1538, 842, 4.5. But your putting it near Dagnor's Cauldron identifies the object. It is the Skeleton Tower of Butcherblock Mountains. It is a playground for baby Paladins. There is a small room inside at ground level, but also a player may ascend the hill behind it and leap over onto the roof and then leap down - a nice playground. But there is MORE... all those little skeletons to kill! For Morit, we have only two little disappointments: the tower is squarish and lacks a peaked roof.
Well, I actually found two objects that it may have been (since the Chessboard was eliminated.) The other was a pair of carved stones near a goblin camp. Now I have to think of something again. This may take a little while.