“A prehistoric site on the border of Nottinghamshire and Derbyshire could become a World Heritage Site. Creswell Crags, a series of limestone caves occupied between 50,000 and 10,000 years ago, has produced numerous tools and unique rock art.”

More here – http://www.bbc.co.uk/news/uk-england-nottinghamshire-12816962 and here -
http://www.themodernantiquarian.com/site/3067/creswell_crags.html
See also – http://heritageaction.wordpress.com/2010/07/08/tentative-list-of-uk-sites-for-world-heritage-status-with-one-missing/