Skyscraping fourteeners, brutal back bowls, turbulent rapids—you’ve conquered all the adventurous terrain at a Coloradan’s disposal, right? Nope. “No matter how far inland you live, [scuba] diving can give you a different perspective on your local environment,” says Kristin Valette-Wirth, chief marketing officer of the Professional Association of Diving Instructors (PADI).

So, although it’s known for its gorgeous peaks, the Centennial State is actually home to a number of intriguing lakes where people can practice diving after getting certified. Here’s how to get certified and start discovering what lies below three noteworthy spots.

How to Get Certified to Scuba Dive

Diving without training isn’t illegal—only dangerous. Get certified at a PADI- or SSI-approved outfit by completing these three phases.

  • Knowledge Development: This is scuba 101—you don’t even enter the water. Via online or in-person lessons, an instructor teaches the basics of diving, such as choosing the right gear and communicating underwater. You must pass a written final exam to move on to the next step.
  • Confined Water Dive: Practice basic scuba skills with your instructor—including getting water out of your mask—in a pool or calm water. Leveling up requires being able to swim nonstop for 300 meters while wearing a mask, fins, and snorkel, as well as floating and treading water for 10 minutes.
  • Open Water Dives: Earn final certification by making four dives, usually over two days, in open water, such as a lake or ocean. (Popular nearby spots include the Aurora Reservoir and the Homestead Crater in Utah.) There, you’ll demonstrate the skills you’ve learned as an instructor observes. Ask your phase two teacher how and when to sign up.

Where to Scuba Dive in Colorado

Aurora Reservoir

Avoid boat traffic by beginning your dive from the designated scuba beach at the far northeast end of the lake. Although you’ll likely encounter suboptimal water clarity that only allows you to see from four to 25 feet (60 to 70 feet is considered good visibility in the Pacific Ocean), spotting the submerged Cessna 310, sunk in 1994 to attract divers, is worth the challenge. Find the buoy marking the vintage plane’s resting place predive.
Before Diving In: Rent gear at Greenwood Village’s One World Dive & Travel, where beginners can take certification classes in the facility’s training pool. Rentals from $100 for 10-day basic rental, lessons from $375

Jefferson Lake

An easy drive up Jefferson Lake Road dead-ends at this chilly alpine lake’s shore, situated at an elevation of 10,000 feet in Park County. Boasting some of the best visibility in Colorado, the lake has views extending up to 40 feet, allowing you to take in the imposing boulders across the bottom and catch the shimmery shadows of kokanee salmon and rainbow trout tailing you through the deep.
Before Diving In: Elevation shortens the amount of time you should spend underwater (and forces you to resurface more slowly); certified divers should enroll in the single-day, $180 altitude-preparedness course at Colorado Scuba Diving Academy in Fort Collins.

Blue Mesa Reservoir

When the government flooded towns and highways around Gunnison to form this hydroelectric power–generating lake 54 years ago, it also created enticing ruins to explore (it’s all foundation now). Rent a boat for better access to submerged bridges and a steep, 100-foot drop-off on the south side of the reservoir.
Before Diving In: You’ll need to BYO gear, as there are no nearby rental shops. But you can hire pontoon boats at Elk Creek Marina, starting at $299 for a full day.