PETERSON AIR FORCE BASE, Colo. (AP) — Hundreds of volunteers at an Air Force base in Colorado were answering questions on Sunday from eager children who wanted to know where Santa was on his Christmas Eve travels.

NORAD Tracks Santa got underway early Sunday morning at Peterson Air Force Base in Colorado Springs, Colorado. It was the 62nd year for the wildly popular program run by the U.S. and Canadian militaries.

Some key facts about the program:

HOW TO GET NORAD UPDATES:

The toll-free telephone number for NORAD tracks Santa is 877-Hi NORAD or 877-446-6723. About 1,500 volunteers answer the phones in shifts throughout Christmas Eve.

The website is www.noradsanta.org, with updates offered in a number of languages in addition to English.

Updates are also posted on Facebook, Twitter and Instagram.

New this year, Amazon’s voice-activated computer service Alexa will be relaying NORAD Tracks Santa updates through the Echo device once the function has been enabled.

HOW IT STARTED:

A Colorado Springs newspaper ran an ad in 1955 inviting children to call Santa but mistakenly ran the phone number for the hotline at the Continental Air Defense Command, which was tasked with monitoring the skies for a possible nuclear attack by the Soviet Union. Children began calling and the CONAD staff happily played along.

The program is now run by CONAD’s successor, the North American Aerospace Defense Command, a U.S.-Canadian command that monitors the skies over both countries.

BY THE NUMBERS:

Last year, NORAD Tracks Santa received nearly 154,200 phone calls and drew 10.7 million unique visitors to its website. It had 1.8 million Facebook followers, 382,000 YouTube views and 177,000 Twitter followers.

By midday in the eastern United States on Sunday, NORAD reported that Santa had delivered around 2 billion presents in Asia, including Christmas Island. NORAD tweeted reminders for “good boys and girls to get to bed” in various countries along the route.