Each spring Ottawa holds a tulip festival and the city that has spent the past three or four months buried in snow comes alive with colour. 
Now some history from wikipedia:
In 1945, the Dutch royal family sent 100,000 tulip bulbs to Ottawa in gratitude for Canadians having sheltered Princess Juliana and her daughters for the preceding three years during the Nazi occupation of the Netherlands, in the Second World War.
The most noteworthy event during their time in Canada was the birth in 1943 of Princess Margriet to Princess Juliana at the Ottawa Civic Hospital. The maternity ward was declared to be officially a temporary part of the Netherlands, so that the birth could formally be claimed to have occurred on Dutch territory. In 1946, Juliana sent another 20,500 bulbs requesting that a display be created for the hospital, and promised to send 10,000 more bulbs each year.