Start with a three-story indoor play structure. Add a trampoline area totaling more than 3,000 square feet, a zero-entry pool, and a full-size turf field. These are just a few offerings at Castle Rock’s new Miller Activity Center (MAC), which opened on October 26 as the keystone feature for the Philip S. Miller Park—the largest park project in the town’s history.

The folks in charge of designing the MAC wanted to make sure it wasn’t just another recreation center—and they succeeded. It’s an ideal spot to bring kids of all ages to burn energy during the winter months, and comes equipped with drop-down batting cages, a golf simulator, and a three-story playground (complete with five-story twisty slide) with ceilings high enough for parents to accompany their tiny tikes. The trampoline park is geared toward kids four and up, and is prime real estate for high-flying basketball games and dodgeball tournaments. The MAC also boasts an impressive indoor aquatics center, with a slide for kids 48 inches tall and up, and a zero-entry section with smaller slide, water table, and vortex whirlpool.

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Jeff Smullen, Castle Rock’s park planning construction manager, says planning for the first phase of the $22 million project began in 2012. Just two-thirds of a mile west of I-25 at the Plum Creek Interchange, Smullen says he expects the park to attract visitors from across the Front Range. “Tourism was one of the goals for the project. We wanted to create a regional draw.”

Philip S. Miller Park’s outdoor space includes a playground with 60-foot slide, seven miles of trails, a 200-step challenge staircase, a turf field, and the Headrush Towers—40-foot and 80-foot towers that kids can climb up, repel down, or even free fall from. Other aspects of the park that will be developed over the next three years include an outdoor zipline, year-around Snowflex park, plaza with splash pad, and outdoor amphitheater.

“There is a lot of excitement for the nontraditional aspects [of the park]: zip lines, Snowflex, and the field house,” Smullen says. “It’s such a large project, and it’s a park that blends into the natural environment.”

The MAC is open on Monday to Friday, 8 a.m. to 9 p.m., and Saturday and Sunday from 8 a.m. to 8 p.m. Admission ranges from $5 to $7 per person and kids under one are free. 1975 W. Plum Creek Parkway, Castle Rock, 720-733-2222,

Follow assistant editor Lindsey R. McKissick on Twitter at @LindseyRMcK.