Lights dancing in the sky and playing in the trees. Familiar paths transformed into a magical wonderland. Hot chocolate and s’mores. A festive, memory-making evening shared with family. For many Arboretum members, attending Illumination: Tree Lights at The Morton Arboretum is an annual holiday tradition.

Celia “Sam” Cieplak of Lisle, a member for more than 20 years, and her three adult daughters have been coming since Illumination began in 2013. Her sister comes by train from Moline every year to enjoy the dramatic transformation of a tree museum into a shimmering garden of colorful light.

This will be the second Illumination for Cieplak’s 18-month-old granddaughter, Meadow. “Last year she was being carried or in her stroller,” her grandmother said. “But she loved the lights. She’s very observant.” This year, Meadow might be big enough to push some interactive light buttons or hug a tree.

Pressing buttons to glow up the trees is always great fun for Diana Suchy’s three grandchildren on the Wednesday evening before Thanksgiving. With her two daughters, “we go in the early evening while my son-in-law stays home in Naperville and makes a nice dinner, because I’ll be cooking the next day,” she said. “It really adds to our holiday.” She’s a big fan of the Christmas season in general—“I’m one of those people who has about four Christmas trees in my house”—and Illumination “just gets you in the holiday mood,” she said.

The route along a paved pathway makes it possible for the whole family to share the fun. Several years ago, when Beckie Saul’s son and his preschool children from California first experienced the Illumination magic, along with her three young granddaughters from Naperville. “We had my mom in a wheelchair and the baby in a stroller,” she said. Saul, of Lisle, is a longtime Arboretum volunteer who attends every year.

Saul also has two grandsons in Chicago who haven’t seen the lights yet, she said, but “This could be the year.”

For these members who are frequent visitors and longtime Arboretum supporters, Illumination transforms the paths and vistas around Meadow Lake and the Conifer Collection that are deeply familiar. “The lights completely change everything, until I could almost say I don’t know where we are,” Cieplak said. “It’s like a brand-new place.”

Everyone agrees that Illumination is even better in the snow. While the Arboretum can’t promise a snowfall, the vivid display of ever-changing color among living trees is perfect for family fun and togetherness.

For Saul, Illumination is a unique seasonal display unlike any other because it’s about the tree-filled landscape as well as the holidays. “It’s about being outdoors with the lights, the music, the hot chocolate, the campfires,” she said. “It brings the Christmas spirit into the night.”