The winter holiday season is back at the Denver Zoo, with tickets for the annual “Zoo Lights” celebration opening to the public on Monday.

For more than a month, the zoo will be transformed nightly into a glowing holiday display, featuring more than 2 million LED lights spread over 80 acres. This year will also feature a new crop of light installations, according to the zoo.

“Zoo Lights” will conclude a full year of festivities as the zoo celebrated its 125th birthday in 2021.

“’Zoo Lights’ is the final toast in a year-long celebration,” the zoo said in a statement. “As the brilliant capstone to 125 Years of Love, our 2021 event promises to be brighter than ever.”

New features include nightly ice-carving demonstrations and light displays of the “Champagne Toast” at the Hospital Plaza, the “Watering Hole” at the Giraffe Meadows and the “Blue Lagoon” in front of the new penguin exhibit.

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During “Zoo Lights,” outdoor animal viewing is limited to cold-weather species, though the Tropical Discovery Building and El Pomar Village Hall will remain open, according to the zoo.

“Zoo Lights” begins Monday and will conclude Jan. 2, running nightly from 5 to 10 p.m. From Monday to Dec. 3, admission is restricted to zoo members only.

Tickets are only available online and in advance at DenverZoo.org. Guests can also purchase packages that include souvenirs, rides and snacks at the event.

Tickets to “Zoo Lights” sell out every year, with limited nightly capacity to enhance the visitor experience, according to the zoo. Guests are encouraged to purchase tickets for their select dates and times as soon as possible.