The home was built in 1908 by Warren Y. Soper, an American-born, Ottawa-based industrialist. Soper was the co-founder of the Ottawa Electric Railway Company -- Ottawa's first public transit system -- and the Ottawa Car Company. Lornado was built on the Soper family cottage property. In homage to one of his favorite novels, Lorna Doone, Soper named the property "Lornado," a name it has kept to this day.
The United States government purchased the property from the Soper family in 1935. From 1935-38, the mansion was slightly modified by the Department of State, but it still maintains many of its Edwardian influences. Despite modernization and refurbishing projects over the years, the interior of Lornado has retained its architectural integrity and much of its original decor. The home still uses some of its original heirloom furnishings and features original artwork on loan from American artists.
The 32 room, two-and-a-half story limestone manor commands a central place on the grounds of the property. The property encompasses ten acres of grounds, including manicured lawns and landscaped gardens, a greenhouse, maintenance buildings, and a gatehouse. Ornamental shelters located below Lornado and several other houses along the Rockcliffe Park Driveway testify to Soper's company's streetcar line, which once traveled this route. Access to the home is via Rockcliffe Road, a restricted access road guarded by the Royal Canadian Mounted Police. Another entrance at Manor Avenue is off limits.
The home is located amongst several diplomatic residences and walking distance to Rideau Hall, the official residence of the Governor General of Canada. Lornado is surrounded by a wall of trees and located above Rockcliffe Park and next to a parkway alongside the Ottawa River.
Lornado was the first diplomatic residence to be established in Rockcliffe Park, and has since been joined by numerous diplomatic residences including the Holy See.
Over the years, many distinguished Americans and Canadians have been guests at Lornado. The list includes many U.S. Presidents and all Canadian Prime Ministers since 1935. American and Canadian visitors have included students, trade delegations, military officers, state governors, congressmen, diplomats, entrepreneurs, academics, bankers, artists, industrialists, educators, and U.S. and Canadian government officials.
Lornado is the venue for the Ambassador's annual 4th of July celebration, when guests (embassy staff, their family and other invited persons) enjoy the spectacular grounds and sophisticated cuisine, mark the anniversary of 1776, hear the anthems of both countries, and witness the U.S. Marine Guards perform their flag drill, the Presentation of the Colors. 
- 190 Coltrin Road - Rockcliffe Park home of the Pakistani Ambassador to Canada
- Earnscliffe - home to the British High Commission in Canada
- Australia House (Ottawa) - home to the Australian High Commission in Ottawa
- Winfield House - home of the American ambassador to the United Kingdom in London
- Deerfield Residence - home of the American ambassador to Ireland in Dublin