It’s been a long time coming, but this week NASA’s Mars Opportunity rovercompleted the first-ever Martian marathon. After landing on the Red Planet in January 2004 on a mission originally planned to only last 90 days, Opportunity has instead endured for more than a decade, and has taken eleven years and two months to travel the marathon-standard 42.195 kilometers. On average, that’s only about ten meters per day—slower even than a snail’s pace.

“This is the first time any human enterprise has exceeded the distance of a marathon on the surface of another world,” says John Callas, Opportunity’s project manager at NASA’s Jet Propulsion Laboratory in Pasadena, California. “A first time happens only once.”