The annual open house weekend, throughout London.  The world’s largest architecture festival, giving free public access to over 800 buildings, walks, talks and tours over one weekend in September each year.

Locally in Lambeth on Saturday only you can visit (moving from north to south):

• West Norwood Cemetery, Norwood Road, SE27 9JU (1-5pm; Cemetery tours at 2pm & 3pm start at the Main Gate (max 40 per tour; arguably the best of the magnificent seven Victorian Cemeteries
• The Clockworks, 6 Nettlefold Place, SE27 0JW (10am-6pm (last admission 5:30pm; hourly tour and workshop demonstration)); internationally pre-eminent clock museum and integral workshops
• Cheviot Gardens, 36 Cheviot Road, SE27 0SU (1-5pm); modern retirement flats:
• 1a Woodland Road SE19 1NS (10am-5pm (last admission 4:15pm; talk at 2pm)); compact flat

And then on Sunday:

• The South London Botanical Institute, 323 Norwood Road, SE24 9AQ (Sunday, 1-5pm (max 50) last admission 4:30pm) history, collections and gardens
• Central Hill Estate (10am-5pm (resident tour every 2 hrs 11am-4pm) ) 1963 Council housing estate

There are 34 properties in Lambeth open over the weekend, and more close by just over the Borough boundaries in Bromley, Southwark and Wandsworth.

Further info.: https://www.openhouselondon.org.uk/