This was a working fire station until 1980. The designated structure has been preserved and moved to Biidaasige Park in 2021 where it reopened in January 2026 as a community building staffed/programmed by the City. During Doors Open, explore the newly renovated building, see original architectural drawings, discover surrounding nature walks, and learn about future developments for the park.

The tennis pavilion at the Ottawa New Edinburgh Club serves as the social and operational hub of the club’s vibrant summer tennis program. Set within a scenic parkland environment near the Ottawa River, the pavilion overlooks a well-maintained collection of outdoor courts and provides a welcoming space for players, members and guests.

Explore the Ontario Forest Research Institute (OFRI), one of the Sault’s most beautifully designed buildings. Constructed with local maple, granite and glass, it offers a unique work environment with natural light and a reminder of its northern Ontario location. OFRI is a Ministry of Natural Resources workplace, supporting forest research related to climate change, genetic diversity, invasive species and more.

Headquarters of the Ontario Heritage Trust, the building features two gallery spaces with mezzanines, an oak-panelled oval board room and a restored manually operated elevator. Often chosen for filming locations, it has appeared over the years in various productions like What We Do in the Shadows and Serendipity. Special programming: Participate in a "plaque-tivity" and make suggestions for future provincial plaques.

Built in 1898, DeCew Generating Station 1 (GS1) is one of the oldest continually running hydroelectric power generating station in Canada. More than 125 years after it was built, GS1 continues to help OPG generate safe, clean, reliable, low-cost power for Ontario. Today, the plant is a working piece of Canada’s hydroelectric heritage.  Pre-registration Required; Onsite Parking Not Available

The Airport Armoury supports 'B' squadron training for members of the Ontario Regiment (RCAC), providing space to conduct vehicle and equipment maintenance, as well as related courses. Speak with members about their roles and experiences within the Canadian Armed Forces.

This museum has been an art, culture and heritage hub in the heart of Orillia for over 25 years. Located in downtown Orillia, the clocktower of the Sir Samuel Steele Memorial Building is a beacon for the museum. The museum’s mission is to provide inclusive space to engage community, inspire creativity and celebrate culture, by exploring art and history.

The Oro African Methodist Episcopal Church, built in 1846-49, is a designated National Historic Site. It is one of the oldest African log churches still standing in North America, standing as a testament to both the Black settlers who carefully maintained it for nearly 75 years and the passionate community volunteers who have worked diligently to preserve it.

Built in 1874 by local builder Thomas Orr Sr., this elegant Italianate home features tall arched windows, decorative brickwork and wide eaves with ornate brackets. Once a private residence, it now serves as the Orr Insurance & Investment head office, reflecting Stratford's rich architectural heritage and the Orr family's long-standing community legacy.

Osgoode Hall — home of the Law Society of Ontario and the highest courts of the province — opened in 1832 and remains a Toronto landmark and symbol of the law in Ontario. The 1867 fence, renowned for its peculiar gates, surrounds the property and its landscaped grounds. Download the self-guided tour or speak with the knowledgeable volunteers. (No tripods allowed.)

Operating since 1973, the Osgoode Township Museum presents the story of Ottawa South’s agricultural and rural heritage. The main museum building is a mid-century two-room schoolhouse that holds the collection of nearly 11,000 artifacts. Explore the galleries, gift shop and research library during your visit. Then step outside and wander through the Agricultural Barn and discover their vast farming collection.

The Oshawa Executive Airport is an aviation gateway to the City of Oshawa and the Greater Toronto Area. Located on 484 acres of land, the airport supports corporate business travel and general aviation with a modern terminal building, dual runways and modern navigational aids. Attractions include Canadian Airforce flyovers, static aircraft displays, and airport bus tours.

For decades, theatre productions came to life in borrowed halls and makeshift spaces. That changed in the 1970s when the Oshawa Little Theatre purchased a former industrial building and transformed it into a dedicated creative hub. By 1983, the dream became reality with the opening of the current theatre. Come and take a behind-the-scenes look at this popular venue.

This museum features restored Victorian-era homes, situated on their original foundations. Henry House showcases a traditional Victorian home, depicting family life in the 1870s. In contrast, Guy House features a gallery and gift shop. Each home belonged to prominent harbourmasters from the area. Visitors can enjoy self-guided tours of Henry House, where costumed hosts are available to answer questions.

Forming part of Oshawa's Civic Centre, this library was a gift of Col. R.S. McLaughlin in 1954. Architect Arthur Eadie was influenced by Frank Lloyd Wright in his design of the McLaughlin Public Library, now the central branch. Explore captivating videos, photographs and memorabilia or attend a guided tour showcasing the library’s evolution over the past 70 years.

The Ottawa Art Gallery (OAG) is home to the art and artists of the Ottawa-Gatineau region, now housing a collection that numbers over 1,450 works — including paintings, sculpture, graphic arts, photographs and new media. In April 2018, OAG opened this modern purpose-built space. The gallery explores and reflects on diversity and social change through a spectrum of visual arts practices.

The Maplesoft-Jones building is home to Ottawa's only Community Cancer Hub, where they are transforming supportive cancer care through dynamic collaborations with diverse community partners. They empower people living with, and impacted by, cancer on every step of their journey. And the Cancer Survivors Park is a beacon for those making their way to The Ottawa Cancer Foundation.

The building that stands at 430 Gladstone was built in 1910 as a Livery (horse and carriage depot) to support one of Ottawa`s top hotels, The Alexandria. Ottawa City Woodshop purchased the property in 2024, providing a home for unban woodworking in the heart of Ottawa.

Founded in 2019, the Ottawa Glassblowing Co-op is located in the heart of Ottawa near Little Italy. Their mandate is to foster a glassblowing co-operative that operates inclusively to support the artistic creativity, learning and growth of its members and to educate the public in the art of glass. Come and see glassblowing demos by local artists!

Jump inside the blueprints to tour a full-scale, furnished mock-up of the patient room-of-the-future and other key room designs for The Ottawa Hospital’s new campus. Guided tours by hospital planning staff will take you behind the scenes of Ottawa’s state-of-the-art hospital plans and how we’re designing spaces. Tours are available in English and French. Registration required.

The Carleton County Jail was built in 1862 and was run as a prison for 110 years, with room for approximately 150 prisoners. In 1972, the jail was shut down due to inhumane conditions. But it was repurposed and opened a year later as this hostel. After a night in a real cell block, you can visit Ottawa’s main sites.

The Ottawa Little Theatre, founded in 1913, is Canada’s longest continuously running community theatre. During Doors Open Ottawa, visitors will receive a guided, behind-the-scenes tour from one of the theatre’s dedicated volunteers. The tour will reflect an actor’s experience from first rehearsal to opening night and feature the talented production team who support them on that journey.

The Ottawa Muslim Association and the Ottawa Mosque was incorporated in 1964 as a charitable organization, with its first phase completed in 1970. The Ottawa Mosque is the first and the oldest mosque in the city, and is one of the oldest in Canada. Its distinct architectural design includes a two-storey prayer hall, library, minaret, central dome and multi-purpose basement.

Opened in 2005, the 9,290-square-metre (100,000-square-foot) Ottawa Paramedic Service Headquarters is a state-of-the-art facility that houses all paramedic operations (except for medical dispatching), a vehicle depot and administrative area for the service. This was the first LEED-certified building in Ottawa. Each day, more than 75 emergency vehicles are deployed to serve the communities of the nation’s capital.

Located in the ByWard Market, this school is in a four-storey, three-bay stone building of solid appearance with a richly decorated principal façade. During Doors Open Ottawa, visitors can join school staff and students in the lobby as they celebrate the school’s 145th anniversary, or take a guided tour. Throughout the day, art and artifacts will be on display.