Notre Dame Cathedral Basilica (385 Sussex Drive)
 
This is the oldest church in Ottawa. The first Catholic masses in Bytown were celebrated in 1827. In 1832 the first chapel, built out of wood and called St. James the Greater, was shared by the Irish and the French-Canadians. A stone church that would eventually become a cathedral was constructed in 1842; it was consecrated as Notre Dame of the Immaculate Conception in 1853 and elevated to the rank of basilica in 1879. Notre Dame Cathedral is an important monument historically, architecturally and artistically. Begun by the pioneers of Bytown, its construction took half a century, from 1839 to 1885. The priest and architect Georges Bouillon designed the interior ornamentation for the neo-Gothic church. 

Notre Dame Cathedral is one of the jewels of Canada’s religious heritage. Its sanctuary and wooden interior, carved by sculptor Philippe Hébert, are particularly noteworthy. In 1978 it was officially designated a Canadian historic monument. From 1999 to 2001, this heritage jewel was extensively restored and renovated at a cost of nearly $10 million.