Ottawa is a little unusual in that it has two Roman Catholic Basilicas - one for the Irish community, the other for the French. This is the French Basilica.
The building was originally constructed in the 1840s, and the tin steeples - were added two decades later. The rich interior of the Basilica is heavily decorated and contains numerous shrines and sculptures. Notre Dame has been the Cathedral for the diocese since 1847, and was made into a Basilica in 1879.
The Basilica is just across the street from the National Gallery at 375 Sussex Dr.
For those that like touring cathedrals, the Canadian Capital won't disappoint with the Notre Dame Cathedral. Here is a picture I took and some information I found for you :-)
In 1978, both the National Capital Commission and the City of Ottawa officially recognized the Notre Dame Cathedral Basilica of Ottawa as an historic monument. The cathedral is indeed the oldest surviving church in Ottawa. It stands on the site that was occupied by the first Catholic chapel open to both anglophones and francophones of Bytown.
The first plan dates from 1839. The work on the building's structure was conducted between 1841 and 1865, and the interior ornamentation, from 1876 to 1885. Missionnaries on temporary postings initiated the actual construction. It was only after the arrival of the Oblate Fathers in 1844 that the work proceeded on a regular basis.
In 1847, the poor mission church was prematurely transformed into a cathedral, the seat of the first Bishop of Bytown, Most Reverend Joseph-Eugène-Bruno Guigues, O.M.I. With the growth of the diocese under the second Bishop of Ottawa, Most Reverend Thomas Duhamel, and with the impetus of a visionary artist, Canon Georges Bouillon, the cathedral was finally completed in 1885. Dedicated to the Immaculate Conception in 1853, Notre Dame Cathedral was elevated to the status of basilica in 1879.
In 1999, the Cathedral underwent a major restoration. This was the first phase of a multi-year project.
Favorite thing: This very impressive cathedral is located at Sussex Drive, near to the Alexandra Bridge which spans across the Ottawa River. There are also several other smaller cathedrals in Ottawa.