Malmesbury Abbey will cost millions to repair
An abbey is in need of £3.5m of repairs and has been added to Historic England's Heritage at Risk Register.
Attracting 65,000 visitors each year, Reverend Oliver Ross called Malmesbury Abbey a "jewel within the nation".
Among the list of repairs, the roof is leaking and carvings around the porch need protecting.
Other Wiltshire sites to be added to the register are Roche Old Court and several ancient barrows.
Malmesbury Abbey is a Norman building which dates from around 1180. It has been a Christian site since the 7th century when a monastery was founded.
Mr Ross says while it does not look like the abbey is currently in danger, without repairs things could get worse.
He wants the abbey preserved for generations ahead.
Historic England's head of places of worship strategy said the disrepair showed "even very hard-working congregations struggle to maintain historic places of worship, let alone cover the cost of major repairs".
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