Using the hoe to raise ground will cost 2 stone for each application and the game engine currently limits a pillar to 10 such applications although I will waste at least one use of the hoe at the very top to insure I get a square surface there. Unfortunately the game engine will cost you 2 stone even if the pillar grows no further so players should keep some level of count as they use the hoe in raising ground. The base of a terrain pillar is 1.5 of the split rail fence pieces so if a player lays out dimensions of 18x18 fences they will get 12 such pillars on each side of a plateau. This should result in use of 2880 stone rather than 8000 stone that I noted earlier so my play experiment likely used more with inefficient use of the hoe. As blprice61 notes, you can get much more mileage if you make a sparse matrix of pillars and interconnect them with beams of some vintage. In any case, terrain columns or terrain plateaus give the player a fairly safe platform to build homes, farms or foundry bases upon.