The Calderstones - Calderstones Park, Liverpool (particularly relevant to Julian, I suppose). These stones are now set up in a circle in a glasshouse in Calderstones Park, Liverpool. They are the remains of a neolithic passage grave which was destroyed around 150 years ago. The stones have many carvings, mostly of spirals and concentric circles, but particularly important are the carvings of human feet, which link the tomb to the Irish passage graves of the Boyne Valley (Newgrange etc) and a couple on Anglesey (Bryn Celli Ddu, Barclodiad Y Gawres)
The stones are not particularly impressive viewed from outside the glasshouse. However, if you get permission from the Head Ranger to enter (which is freely given, but must be in advance), close-up they are fascinating.
MAGIC (Record No.: 23692) describes the site as the remains of a destroyed Neolithic chambered tomb, now arranged in the form of a stone circle:.
The monument is known as the Calderstones, a group of six decorated sandstone monoliths thought originally to have formed part of a Neolithic chambered tomb constructed approximately 4,000 years ago. These stones have been removed from their original context and are now arranged in a circle and located in the vestibule of Harthill Greenhouses in Calderstones Park. They display an abundance of prehistoric rock carvings and were closely examined by Forde-Johnston in 1954 after their removal from an earlier location close to the entrance to Calderstones Park where they had been erected for display in 1845. They were erected in their present location in 1964 and placed in a random order.
The eight digit grid reference for this site is SJ40408761.
The Transactions of the Historic Society of Lancashire and Cheshire for 1865 has an article by Professor J Y Simpson about the carvings (with drawings). I guess the feet hadn't been spotted yet. Perhaps they come under the description of the stone which is "too much disfigured by modern apocryphal cuttings and chisellings to deserve archaeological notice."