The Ness of Brodgar site has been under excavation since 2004, revealing a massive complex of monumental Neolithic buildings dating from the centuries around 3000BC.
Provided their funding plans come together, the seven-week excavation will be open to the public on weekdays between July 5 and August 16. At present, guided tours are pencilled in for Monday to Friday at 11am, 1pm and 3pm.