This state-of-the-art building, located within the Earnscliffe National Historic Site, has been the official residence for British high commissioners for more than 90 years. The building has LEED Gold status, with reduced water consumption inside and native and drought-resistant vegetation throughout the grounds. Note: Due to renovations, the High Commissioner’s residence will not be open, but the grounds will be.

Experience nature's gifts at Bruce's Mill Conservation Park. Walk along the forest trails, admire the high tree canopy, and practise your swing on the driving range. Learn more about the park and conservation! During Doors Open, enjoy a tour or take a guided hike of the conservation area. Entrance fees to be waived for Doors Open Whitchurch-Stouffville.

The Bytown Fire Brigade Historical Society is a volunteer-based non-profit corporation dedicated to preserving, interpreting and celebrating the history of firefighting in Ottawa. They collect and maintain historical firefighting artifacts — including vintage fire trucks, uniforms, equipment and photographs — illustrating the evolution of firefighting technology. Through its efforts, they help preserve Ottawa’s firefighting heritage for future generations.

Take a behind-the-scenes tour of Ottawa’s oldest stone building. The Bytown Museum offers tours of the Commissariat Building throughout the day. Come check out their new temporary exhibit and award-winning gallery renewal, a showcase of their historical costume collection and their vault. Enjoy a fresh lemonade next to the Ottawa lockstation, part of the Rideau Canal UNESCO World Heritage Site.

The ByWard Market has been Lowertown’s focal point since 1848. This particular site has served as a market since 1875. The present building is the fifth to house the market. Home to food merchants, specialty boutiques and artisans operating in indoor and outdoor spaces, the ByWard Market Building is a landmark. For Doors Open, enjoy special tours, displays and presentations.

With over 17,000 artworks by over 3,000 artists, the Canada Council Art Bank houses the largest collection of contemporary Canadian art in the world. The collection houses paintings, sculptures, drawings, photographs and prints by emerging and established artists, including a significant number of Indigenous artists. The collection is also regularly featured at the Canada Council for the Arts main office.

The Canadian Conservation Institute (CCI) and the Canadian Heritage Information Network (CHIN), part of the Department of Canadian Heritage, were created in 1972 to advance and promote the conservation of Canada’s heritage collections. The building houses over 20 laboratories, metal and wood workshops and over 100 offices. Don’t miss “Captain Conservation,” an imposing fiberglass sculpture over the front entrance.

The Ottawa Hospital is a world leader in cancer research. During Doors Open, discover fascinating cancer research with a behind-the-scenes tour of a lab, and an opportunity to explore the lab’s high-tech tools. For safety reasons, visitors must be 16 years or older. Forty-minute guided tours leave every hour from the Cancer Centre lobby. Space is limited. Registration is required.

This Centre operates in a beautiful historical building in downtown Ottawa. They provide evidence-informed integrative medicine, research and education across the spectrum of chronic and acute health-care conditions — such as cancer, cardiovascular health, mental health, thyroid health, women’s health, diabetes and more. Their approach emphasizes quality of life, support for the body, care of the spirit and active disease prevention.

The Centretown Mosque was constructed in 1911 as the First United Church — the site of Canada’s first mixed-raced marriage. Since then, it was also the Ottawa Chinese-Canadian Heritage Centre. Today, it is the first mosque to serve Ottawa’s Muslim community. Fundraising campaigns are currently underway to help preserve the site’s history — including two beautiful halls, an organ and stained-glass windows.

Built in 1872, this church was constructed to harmonize with the new Parliament buildings. Named the Cathedral of the Diocese in 1897, it continues to nurture faith in creative and traditional ways. Architectural features include soaring ceilings, magnificent windows and the bell tower, home to the 516-pound bronze bell cast for the original church in 1839.

St. Bartholomew’s Anglican Church was built of local limestone. It remains an active place of worship and a concert venue today, with a history that’s closely intertwined with that of the local community, the city of Ottawa and the nation. Artifacts and windows remind us of those connections — particularly the stained-glass window behind the altar and the magnificent Létourneau organ.

This church is notable for its exquisite local stained glass dating from the early 20th century to the 1980s. Their windows illustrate some of Ottawa’s early stained-glass works, with a strong influence by Tiffany. The building also tells the story of a creative and tenacious congregation that has had a spiritual home in what’s now Old Ottawa East since 1877.

The Rideau Township Archives began as North Gower’s town hall in 1876 until new township offices opened in 1967. It is interesting for its history and its architecture – featuring an unusual cupola. After being restored, it was among the first of the township’s buildings to be designated. The current exhibit features this initial revitalization in the 1980s.

In 1975, CKCU became the first campus-based community radio station in Canada. It continues to be a pioneer in community broadcasting, serving as a voice for many Ottawa identities and communities not served by the mainstream media. Offering over 100 programs in over 10 languages, CKCU is committed to diversity. Come witness live radio in the making!

In 1960, NATO and the Canadian Department of National Defense built a satellite communications facility here that provided communications between all NATO countries until 1999 when the site was decommissioned. In 1999, it was purchased by Canadian Space Services Ltd. to serve as its corporate headquarters. Today, interior space is rented to local businesses for meetings, workshops and parties.

The Cumberland Heritage Village Museum provides visitors with an immersive, seasonal experience that showcases rural life in the 1920s and 1930s in Eastern Ontario. Tour an operational sawmill and blacksmith shop, an old train station and caboose, a one-room schoolhouse, a print shop, a 1927 Imperial Gas garage, a 1904 church and several family homes and barns.

This award-winning building serves a representational role for the Ismaili Imamat in Canada, offering a centre for building relationships, enabling quiet diplomacy, and disseminating knowledge and information, while reflecting the humanistic/humanitarian agenda of the Aga Khan Development Network and its associated institutions. Inside, the play of light on transparent and translucent surfaces creates a dynamic visual effect.

Nestled in the heart of Manotick Village, Dickinson Square shares a remarkable past rooted in Canadian history and industrial ingenuity. Run by Watson’s Mill Manotick Inc., Dickinson Square comprises two sites: Watson’s Mill and the Dickinson House Museum. This heritage home explores the lives of the past mill owners. After touring this historical museum, check out the adjacent mill.

The Diefenbunker is Canada’s most significant surviving Cold War artifact. It is an impressive four-storey underground facility that operated as the country’s central communications headquarters during the Cold War, ready at any moment in case of a nuclear attack. Now a museum, the Diefenbunker offers a one-of-a-kind experiential learning environment, coupled with award-winning programs, events and exhibitions. Registration required.

The Dominion Observatory Campus consists of several scientific buildings used for astronomy, seismology, gravity and geo-magnetism. In 1904, the first building was constructed to house the retractable telescope. In 1905, a transit house was added to the western wing for the meridian circle telescope and transit instruments that were used to determine time, longitude and star positions.

This church, designed by architect Konstantinos Zourdoumis and constructed in 1975, is a fine example of the neo-Byzantine style with its classic domed structure. Highlights include hand-painted Byzantine icons on the domed ceiling and walls, a hand-carved wooden iconostasis wall in front of the altar, and beautiful mosaic tiles.

In 1866, Mother Marie of the Order of Our Lady of Charity came to Ottawa to conduct mission work in a building on this site. By 1877, a spacious new monastery building was constructed, which was further expanded in 1895. Following a devastating 1938 fire, the monastery was rebuilt. In 1972, the Chinese government purchased it as Chinese Embassy’s chancery.

Since the late 1940s, this building has housed three embassies — the Uruguayan Embassy, the Embassy of the Hungarian People’s Republic, and the current one. In 1995, the mansion was purchased and donated to the Republic of Armenia by a prominent Armenian-American businessman and philanthropist. Each year, they welcome hundreds of visitors interested in architecture and Armenian history.

Known as Toller House, this building was designed by Henry Horsey and J. Sheard in the domestic Gothic revival style. Many dignitaries lived here, including Frederic Toller, Auditor General of the Dominion’s Currency in the 1880s. In 1999, it opened as the Embassy of Croatia following an award-winning restoration. Guided tours will be offered for the ground level only.