London and North Western Railway boundary marker at Buxton, Derbyshire. There were two of these in the wall that runs beside the main road along Ashwood Park. Unfortunately, they disappeared some years ago when the wall collapsed at various places.

Boundary markers (including the LNWR) were usually cast iron, but some railway companies (including the Stockton and Darlington) used stone.

Limestone.

Photograph ©R.McNab