Montreal’s original metro cars reached their final stop on Thursday, 52 years after first going into service.

“It’s an old train, we had the oldest fleet in the world at one point,” said STM President Philippe Schnobb.

The MR-63 train cars were originally rolled out for the metro’s grand opening in 1966, one year before the world got to ride them at Expo ’67. They were designed by industrial designer Morley L. Smith, his first job out of university.

Smith was on hand to see his creations roll quietly into retirement.

“Most cars then were square boxes with straight sides, they had no relation to a vehicle,” he said. “I managed to make the walls curved, which gained six inches of width.”

Riding in one of the outgoing cars, he said he was surprised they’ve lasted 52 years – roughly double their initial life expectancy.

“I thought it was 25 years, but they’re well maintained and they run inside instead of outside, so no weather exposure,” he said. “They seem to be okay, though 52 years is a long time.”

Well maintained or not, after a half century the issues have started to pile up. In February, 2016, the STM began rolling out the new, more comfortable Azur cars as service interruptions began piling up due to malfunctions in the older ones.

“That’s been one of the challenges of the metro in the past years: the reliability, the comfort,” said Quebec Transport Minister Andre Fortin. “People want to make sure when they get on the subway system, they know what time they’re going to be downtown or at work.”

Each MR-63 has travelled approximately 4 million kilometres, the equivalent of the farthest point of orbit between the Earth and Mars. Such intrepid travelers deserve to retire in style. In 2016, the STM announced a program that will see the MR-63s turned over for special projects. Some have been transformed into galleries, others into restaurants and pop-up shops. But Schnobb said a few will stick around, just in case.

“We will keep three cars in the network that could run as well for some special occasions,” he said.