Visitors can learn about printing techniques in Coupar Angus
More than 100 buildings across Dundee and Perth and Kinross are opening up to let people explore for free.
Doors Open Day events are taking place throughout the weekend.
In Dundee, people can visit the restored buildings of Gardyne's Land, the North Carr Lightship, Claypotts Castle and the city's Central Mosque.
In Perth and Kinross, people can go inside Dunkeld Bridge, visit St Magdalene's Gunpowder Store and hear about the early printing industry.
Sarah Winlow, who is co-ordinating the events in Perth and Kinross said: "This is the biggest event that we've had in Doors Open Day Perth and Kinross.
"Seventy events are going on, that includes buildings as well as guided walks, a cycle ride, lots of music is going on as well.
"It gets people interested in history, gets people to learn about their local environment.
"It's a really rich cultural heritage resource that we have here in Perth and Kinross and the programme illustrates that beautifully, we've got some really old buildings and some quite unusual landmarks taking part."
St Salvador's Episcopal Church is seen as one of the "hidden gems" in Dundee
Adam Swan, who is organising the event in Dundee, said: "It's the one weekend in the year when buildings which aren't normally accessible to the public are open free of charge.
"It can satisfy your curiosity as to what's behind the facade, it gives you an opportunity to see buildings that you wouldn't normally visit, whether it's a church or the sheriff court, or the city chambers.
"It's an opportunity to find out what happens in them and maybe it would lead people to new interests and new involvement in projects or it just satisfies their curiosity.
"There are so many splendid buildings in Dundee - people really don't know about them - they may have lived there all their lives but how many people have seen the absolutely lavish and very, very important murals and mosaics that are in St Salvador's Episcopal Church up in the Hilltown for instance?"