Task: Question Generation
Input (English): Passage: All of the surviving megalithic tombs from the Early Neolithic period have suffered from neglect and the ravages of agriculture. Although Ashbee noted that the Coldrum Stones represent "Kent's least damaged megalithic long barrow", it too has suffered considerable damage, having become dilapidated and fallen apart over the six millennia since its original construction. Most prominently, the eastern side has largely collapsed, with the stones that once helped to hold up the side of the barrow having fallen to the bottom of the slope. Conversely, it is possible that the sarsens at the bottom of the slope were not part of the original monument, but were stones found in nearby fields which were deposited there by farmers.Excavation of Chestnuts Long Barrow revealed that it had been systematically destroyed in one event, and Ashbee suggested that the same may have happened to the Coldrum Stones. He believed that the kerb-stones around the barrow were toppled, laid prostrate in the surrounding ditch, and then buried during the late 13th or early 14th century, by Christians seeking to obliterate non-Christian monuments. Conversely, the archaeologist John Alexander—who excavated Chestnuts in 1957—suggested that the Medway tombs were destroyed by robbers looking for treasure within them. As evidence, he pointed to the Close Roll of 1237, which ordered the opening of tumuli on the Isle of Wight in search for treasure, a practice which may have spread to Kent around the same time. Alexander believed that the destruction in Kent may have been brought about by a special commissioner, highlighting that the "expertness and thoroughness of the robbery" at Chestnuts would have necessitated resources beyond that which a local community could probably muster. Ashbee further suggested that in subsequent centuries, locals raided the damaged Coldrum tomb for loamy chalk and stone, which was then re-used as building material.
Output (English): What is the name of the work that Ashbee believes was destroyed by Christians in one event?