Accurately measuring level over long distances?

[Cervaise]

@Chronos

Oh, and you also want to make sure you know what you actually want.

Indeed.

This thread from a little while ago (to which you contributed) discusses one interesting use case.

Does the design of a very large building have to account for the curvature of the Earth?

This question is inspired by a facility being built by Tesla in southeast Austin. I drive by it from time to time and I am struck by how large it is. The building is not very tall, but it is going to cover a very large area. Do the architects and engineers for this car factory have to account for the fact that the Earth is round when designing a building of such a large linear dimension? Is the floor of the factory designed to be truly flat even though the Earth below the foundation is not? …