Alberta Premier Alison Redford says it is a celebration of rebuilding the community and also of remembering terrible days.
Denny Garrett, the reeve of Lesser Slave Lake, thanked people who came from outside the area to help rebuild the town.
The fires destroyed more than 500 homes and buildings, forced thousands of people to flee for their lives at an estimated cost of almost $1 billion.
Meanwhile, Alberta crews were battling two out-of-control wildfires Tuesday and holding three others, including one in the Slave Lake region.
The wildfire threat ranges from extreme to high and Alberta's forests are under a fire ban until further notice.