I am not sure if it has ever been repealed, but it was a legal requirement for railways to locate mileposts every 1/4 mile.
The legislation for the requirement to provide railway mileposts in England and Wales, is to be found in Section 94 of the Railway Consolidation Clauses Act 1845. Section 87 of this act applies to Scotland.
I recall being informed at Railway Training School (late 50s) that without such a system in place, it was not legal to charge for passenger or freight use. Almost every charge raised by the Railway had a mileage element at that time.
