When was the last time you saw a TV commercial come to life? In towns across the U.K., it happens every year when the beloved Coca-Cola Christmas trucks appear, echoing the “Christmas Caravan” ads that first aired 20 years ago.

“Holidays are coming, holidays are coming,” Instagrammed one British celeb, posting a selfie in front of the real-world truck in London as it prepared to head out on tour in late November.

“My all-time favourite Christmas ad,” commented another fan.

The classic Coca-Cola commercial by Michigan-based agency W.B. Doner follows a magical delivery truck as it chugs along to a “holidays are coming” refrain. In the ad, a truck first appears behind silhouetted trees and is soon followed by others, creating a glittering caravan that lights up a town and its families as it passes through.

The commercials, which struck a chord with viewers from the U.S. to Europe, were complemented by actual trucks that appeared in 65 U.S. cities and a swath of Eastern Europe in the late 1990s.

A Tradition That Hits Close to Home

Two decades later, the tradition lives on in the U.K., where, for many residents, the truck’s arrival heralds the official start of the holiday season. That’s the case for Matt Smith, a 28-year-old truck driver with cystic fibrosis who got to take the wheel of the iconic vehicle this year, realizing a dream he’d had since he was seven years old.

“Seeing the delight on Matt’s face when he was behind the wheel reminded me that it’s these moments of happiness that make Christmas special,” said Bobby Brittain, marketing director, Coca-Cola Great Britain.

Back when Smith was a kid, the caravan in the TV ad was created using three prop 18-wheeler trucks that were decorated with 30,000 light bulbs and then transformed and multiplied to twinkling effect by Hollywood groundbreaker Industrial Light & Magic. In the spot, a boy who’s late to the town commotion catches a break in the end, with a soda that materializes out of thin air and a nod from the suddenly animated Santa image on the back of the truck.

In a later version of the ad that aired in 1999, a boy and his grandfather read a story about the caravan in front of a glowing fire. The fireplace morphs into a truck, turning the fantasy into a real-life ride, before the scene returns to the family den with the pair sound asleep.

“Christmas is a family season, and that's what the spirit of the ‘Caravan’ ads is,” says Ted Ryan, Coca-Cola’s chief archivist. It wasn’t until Coca-Cola realized it had a hit commercial on its hands, he explains, that it began to commission trucks that would replicate the experience in the real world.

"As soon as the physical trucks began to visit communities, it made the ads resonate a little bit more," Ryan says.

The Coca-Cola Caravan visits many countries around the world each year. Check out this full-screen gallery for photos from this holiday season.

The Caravan Journeys Into a New Era

The real truck that is currently touring the U.K. through December 23 requires no small effort. According to Louise Maugest, a Coca-Cola brand manager based in Britain, it’s a special one dedicated to the 46-stop tour, and it takes about a month to prepare.

“Every year, we make sure all of the paints look perfect, so we do a little refurbishment so it always looks impeccable,” she says. “This year, we added a few lights on the sides to make the truck look even nicer.”

The truck has other invisible whistles, the hallmarks of a new era: Thanks to credits purchased from Carbon Footprint Ltd., it will offset nearly 15 metric tons of carbon emissions. It also offers options such as Diet Coke, Coke Zero and Coke Life for those limiting sugar consumption.

There’s one stop in the U.K. tour that hasn’t yet been determined. Through December 4, people could enter for the chance to win a home visit from the truck, which will deliver not only drinks but also prizes, including a GoPro camera and Apple products, worth £5,000 (about $7,500).

Coca-Cola Christmas Caravan

Capturing “Magic in the Moment”

Thanks to the truck tour, and the bridge it forms between the past and the TV screen, artist Haddon Sundblom’s defining renditions of Santa that first appeared in 1930s print ads and came to life on the magic caravan still endure today.

“It’s that linkage between the real and the digital that doesn’t happen very often, but when it does, it captures magic in the moment,” Ryan says. “It reminds people of the wonderment that can be Christmas."