Extra security is being put in to foil vandals at a listed building which was the scene of a prisoner of war escape.
In 1945, 84 German PoWs tunnelled out of Hut Nine at the former Island Farm prison of war camp in Bridgend.
But it has become a haven for vandals who have targeted the building.
Bridgend council has now secured funding to improve security on the site, where last week planning councillors approved proposals for a sports village.
Plans to turn it into a heritage attraction have long been considered.
But such hopes have not been helped as a colony of protected lesser horseshoe bats roost inside.
Vandals have exacerbated the situation, according to a report to the council, which owns the building.
It says the authority has been successful in obtaining a grant from the Countryside Council for Wales.
Security shutters are to be fitted to windows and doors "to ensure the protection of the bat roost but also to prevent further intentional damage to the structure".
Multi million-pound plans to turn the former PoW camp and surrounding farmland into a sports village were approved in principle by councillors on Friday.
Developers are proposing creating improved access to Hut Nine as part of their wider plans for the site, which include a 15,000-seat rugby league stadium, and separate rugby union and football stadia.
Below the hut, 84 PoWs escaped after digging a 60ft (18m) tunnel in March 1945, sparking a massive manhunt.
Three made it as far as Kent but others were not as successful. One group stole a car and found themselves lost in Cardiff, according to some of the former PoWs who returned to the site in the 1970s.
Local historian Natalie Murphy said not much was left of the PoW camp but what was left behind was an important reminder.
Before the camp was flattened, some artefacts were retained for posterity, including graffiti daubed on the walls of buildings by inmates.
She said: "It is really important and it will be great if we can keep Hut Nine going.
"The tunnel is still intact - there is a lot of history and it should be redeveloped.
"It's history we really want to keep - Hut Nine is a piece of history and we want to keep it that way."