The Canadian Tulip Festival is a tulip festival held annually each May in Ottawa, Ontario, Canada. The festival claims to be the world's largest tulip festival, displaying over one million tulips, with attendance of over 650,000 visitors annually.

Large displays of tulips are planted throughout the city, the largest of which are often in Commissioners Park on the shores of Dow's Lake and along the Rideau Canal, with 300,000 tulips planted there alone.

The festival is a cultural and historical aspect of the special Canada–Netherlands relationship, having originated with commemorative donations of tulips to Canada from the Netherlands for Canadian actions during World War II, when Canadian forces led the liberation of the Netherlands and hosted the Dutch royal family in exile.

The Netherlands continues to send 20,000 bulbs to Canada each year (10,000 from the royal family and 10,000 from the Dutch Bulb Growers Association).

According to en.wikipedia.org