More than 40 buildings across Cork City, many of which are not normally open to the public, will throw open their doors for free tours on Saturday.

And with more than 100 free events lined up, this year’s Cork Heritage Open Day is set to be its biggest yet.

The city council’s heritage officer, Niamh Twomey, said the event has gone from strength to strength since it began in 2005 to mark Cork’s designation as European Capital of Culture.

“Cork Heritage Open Day really demonstrates the diversity of the city’s heritage through an exciting line up of walks, talks, events and building openings,” she said.

“It’s a great day out for all the family and those of all ages, and it doesn’t cost a penny.”

This year’s Cork Heritage Open Day recognizes the 20 yr anniversary of Rory Gallagher’s death #corkhour #corkheritage — Cork Heritage Open Day (@corkheritage) August 17, 2015

This year’s event will mark the 20th anniversary of the death of music legend Rory Gallagher, with walking tours led by Marcus Connaughton, author of several books on Gallagher’s life and this year’s Cork Heritage Open Day Ambassador.

Elizabeth Fort, off Barrack St, will host a ,edieval family-fun day with historical re-enactments and displays of weaponry, pottery, archery, and medieval games.

This day next week is @corkheritage Open Day! Grab one of these to see what's happening here and across #Cork City pic.twitter.com/EjTHZrDv1C — Elizabeth Fort Cork (@ElizabethFort_) August 15, 2015

The Cork City and County Archives will open its doors to showcase the ‘Moments in Time: 1915 Archives of Cork’ exhibit, which charts the visit of Padraig Pearse to Cork a century ago — on August 22 and 23, 1915.

Historian Tom Spalding will lead what been billed as Cork’s shortest walking tour, which packs 250 years of history into a 800m stretch on and around the city’s Grand Parade.

Other walking tours include the Cork Music Scene and Sir Henrys Tour; Being Boole, which marks Boole’s bicentenary; the Origins of the Quakers in Cork; and a bug and ladybird hunt for children.

There are several self-guided walks exploring various facets of the city’s heritage from steps and steeples, featuring landmark buildings and spectacular views from the north side, to customs and commerce, which follows the river to showcase some of the old and new buildings in Cork City.

A medieval and modern themed walk will take participants through what were once medieval lanes, and a saints-and-scholars themed walk on the city’s south side.

Cork Heritage Open Day marks the start of Cork Heritage Week, with full details of all events on www.corkheritageopenday.ie, Facebook, or Twitter.