Didn’t the kinda do that in Behind The Curve?
They used a long body of water as a flat reference, set up 3 columns with a hole through them at the same height above the water reference.
A torch shone through 1 end should be visible at the other end if all of the holes are on the same plane.
Because of the curvature, they had to lift the last column to be able to see the light.
They didn’t manage to explain that one