Every September, more than 40,000 volunteers across England organise as many as 5,000 events in celebration of the country's wonderful history and culture. It marks a great opportunity to explore hidden places and unique venues, all of which are free to explore. A full list of events taking place in and around Milton Keynes can be viewed on the Heritage Open Days website, but here are 21 not to miss.
The national Heritage Open Days will see a wealth of venues in and around Milton Keynes open their doors to visitors this month.
Andy Stagg, courtesy of Bletchley Park Trust
All Saints Church Bow Brickhill
Milton Keynes City Discovery Centre