Funnyman David Letterman celebrated his son’s birthday Saturday on the Durango & Silverton Narrow Gauge Railroad.

A private train went from Durango to Cascade Canyon – a partial trip that runs in the fall and winter months, said D&SNG owner Al Harper.

Six adults and four kids celebrated Harry Letterman’s birthday, Harper said. Harry turned 8 on Nov. 3.

Harper gave Letterman, 64, a tour of the museum and the roundhouse.

“He could not have been nicer,” Harper said. “Very humble. His wife and family are very outgoing. He’s a little more reserved.”

Letterman told a hostess that he loved the train and loved Durango and planned to talk about his trip on his show “Late Night with David Letterman.”

Other celebrities have ridden the train, including one of Letterman’s favorite targets, Oprah Winfrey.