Hi, We have a vertical cave that is just over 100 metres deep, with its entrance just below a 100 metre contour. We want to show a grid on the elevation view, like this: #show an altitude grid every 25 metres #("50 50" affects only plan view, so is ignored here) grid bottom #behind the cave grid-size 50 50 10 meters #one line every 25 metres of depth grid-coords border #show numbers at the edge of the survey This leaves a 20+ metre gap at the bottom, since the cave only just made it past the last 25 metre grid line. 1. Is there a way to cut off the grid after a certain amount, so that it doesn't show the blank gap at the bottom? Or alternatively, cut off the grid after the cave ends? Or "show the next grid line if the cave is within 5 metres of it"? 2. Is there a way to start the grid at "0" at the entrance to the cave, in order to show depth below the entrance instead of the altitude above sea level? I tried this: grid-origin 0 0 400 meters But Therion just threw an error with no error message, so I am obviously doing something wrong. Does that only work in plan view perhaps?