A massive snow fort constructed in the northwest community of Royal Oak was removed by city workers on Thursday afternoon following a 311 complaint by a concerned citizen.

The structure was created out of a mound of snow which remained along Royal Oak Green N.W. after city road crews cleaned neighbourhood streets earlier this month. The fort, which is believed to have been built by a group of Royal Oak children, included a tunnel and a stairway to the top.

"It does take over some of the parking on the street but otherwise it's good that the kids are enjoying it and making a little snow tunnel through it and enjoying themselves,” said Royal Oak resident Karen Strutynski. “As long as it's safe, I think everything is positive about it.”

On Wednesday, an unknown citizen reported the fort to 311, questioning its safety:

‘A snow pile left after the city clearer the roads has been turned into a playground. While very cool and inventive I am concerned about the safety of the younger kids should the roof give way. Can you check this structure.’

The snow fort was inspected by a City of Calgary Parks foreman on Thursday afternoon.It was determined the fort was susceptible to collapse given recent and forecasted warm temperatures.

As of 5:30 p.m. Thursday, the fort ceased to exist.

City officials say they continue to encourage citizens to engage in outdoor winter activities but public safety remains paramount.

In January of 2014, a young boy in Winnipeg lost his life after he was crushed by a snow fort which collapsed.  In February, a 9-year-old boy was rescued from a snowbank near Orangeville, Ontario but succumbed to his injuries in hospital.