More than 80,000 visitors are expected at nearly 130 buildings which will be open, free of charge on June 1 and June 2.

An annual opportunity to explore a side of Ottawa that is rarely available to the public, is back.

Doors Open Ottawa 2019 gets underway Saturday June 1 and runs through the weekend.

More than 80,000 people are expected to explore some of the city's most interesting places.

Residents and visitors will have access, free of charge, to nearly 130 buildings across the city, including 10 sites that were not included in the 2018 event.

Some of this year's Doors Open Ottawa highlights include:

The Algonquin College DARE district

The National Arts Centre

The Official Residence of the Embassy of Denmark

Ottawa Paramedic Service Headquarters

Ottawa Police Service Professional Development Centre

Select Ottawa fire stations

Behind-the-scenes tours are also available at:

Government buildings

Research facilities

Heritage buildings

Artists' studios

Places of worship

Embassies and high commissions

Doors Open invites you to share your experiences on Instagram, as part of a photo contest. For more information, including the full list of participating buildings, visit ottawa.ca/doorsopen.

There will be a free, accessible OC Transpo shuttle bus, giving visitors access to nearly 50 participating buildings from the eight stops along the shuttle loop.