Parliament Hill's world famous cat sanctuary is shutting down after more than 50 years.

Cats were originally used on the Hill as a means of pest control, and at one point nearly three dozen felines lived there, all cared for by volunteers and donations.

Tourists even flocked to see them after Rene Chartrand, known as the "Cat Man," built tiny condos for the cats to live in, complete with green shingled roofs.

But over the years, spaying and neutering reduced the colony size, and now just four cats remain.

The remaining cats are getting too old and fragile for the Ottawa winter, so volunteers have decided to take them home and disband.

“It’s a bittersweet thing, but all good things come to an end,” volunteer Jackie Barlow said.

Another volunteer, Brian Caines, said he's adopting two of the cats and the others have already found home.

"And they'll just ‘lead the life of Riley,’” he said.

For now fans can still admire the cats online.

A Facebook page with more than 4,000 fans is calling for something permanent.

One fan suggests "having a statue built" of the cats.

Another has "no desire to visit the politicians in Ottawa, but would love to visit the sanctuary."

With a report from Richard Madan in Ottawa