Dinosaurs roamed the volcanic buttes formed 65 million years ago in Golden — and there are still traces of them everywhere. The first T. rex specimen was discovered on South Table Mountain, and if you're interested in playing paleontologist, hop onto the Camp George West trailhead for 4.1 miles of low-key scenic hiking with panoramic mesa-top views and plenty of dinosaur tracks for those who are looking. Just remember to stay on the trails, as undesignated paths degrade the mesa ecology.

Less than fifteen miles from downtown Denver, the free and open-to-the-public Rocky Mountain Arsenal National Wildlife Refuge offers a fresh-air escape on nearly 16,000 acres of grassland, wetland and woodland that more than 300 species call home. You're not going to see them all while wandering the ten miles of easy, flat trails — the meandering 1.8-mile Ladora Loop Trail is a good introduction — but definitely seek out the herd of more than eighty bison and keep your eyes peeled for coyotes, deer, bald eagles, burrowing owls and a plethora of prairie dogs. Folks come here just to fish the small lakes and ponds for largemouth bass and northern pike in an area that attracts a lot of migrating waterfowl as well as a staggering variety of birds, and the floating boardwalk leads to a more tucked-away and quiet space with viewing benches. Time your visit for sunrise or sunset to get the best photo ops, complete with the Rocky Mountains and the Denver skyline.

Readers' Choice: Chautauqua Park

Sometimes it just feels good to spend a night under the stars, but the commitment required to do a multi-day hike can be exhausting. Red Deer Lake Trail, in the Indian Peaks Wilderness just north of Nederland, is just right: a 14.2-mile out-and-back that sits comfortably in the intermediate skill range, with waterfalls, meadows and elk and moose sightings as rewards along the way. The final payoff of the lake itself sits at slightly above 10,000 feet (net gain: 717 feet), with plenty of secluded backcountry campsites. You'll wind up leapfrogging the day-hikers for the first few miles of the four-wheel-drive Buchanan Pass Trail that connects to the Red Deer path, but most of them fall away at the big switchback that veers toward the St. Vrain Glacier. The killer views include several of the Indian Peaks, including Sawtooth, St. Vrain and Mount Audubon, and fly-fisherfolk will find trout in the lake and Middle St. Vrain Creek along the way. A $5 permit per group is required for camping through the Boulder Ranger District.

Readers' Choice: Castlewood Canyon State Park

Indian Peaks Wilderness

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Camping in Colorado is always fabulous, but there's something extra-magical about Rifle Falls, a lush, 48-acre park located thirty miles northwest of Glenwood Springs. Skip the site's thirteen drive-in RV and tent campsites, and opt instead for one of seven walk-in spots laid out alongside East Rifle Creek. All campsites have a table, fire pit and bear-proof storage boxes, and some have electrical hookups, too. For all you glampers out there, restrooms and water pumps are available near the parking lot. The best thing about this campground is an easy-to-moderate hiking trail connecting campers to a seventy-foot triple waterfall overlooking limestone caves. For a longer trek, follow signs to the fish hatchery. Pets are allowed in the campground but must be on a six-foot-or-shorter leash. Rifle Falls is open year-round, and reservations can be made up to six months in advance when camping between April 1 and October 31.

Landlocked Coloradans are always on the hunt for a beach that feels, well, beachy. With its wide swath of soft sand and much-appreciated amenities — bathrooms, a water fountain, and a small but well-stocked cafe that serves crispy French fries — the lake-like setup at the Boulder Reservoir makes for a nice day at the shore, especially on the much-less-crowded weekdays. Friendly lifeguards patrol during beach hours (10 a.m. to 6 p.m. daily), and you can rent kayaks, canoes and SUPs to explore beyond the cordoned-off swim area, which also allows rafts and floaties. Swim out to the floating decks for a little peace and quiet and to watch the herons, pelicans and ospreys that call the rez home. There's a $7-per-person entrance fee, and alcohol in non-glass containers is allowed.

Readers' Choice: Arapahoe Basin

While some people treat river rafting as if it were an amusement-park ride that they just strap into before someone hits the switch, savvier adventurers understand that it's an outdoors experience fraught with unpredictability that could put you way outside of your comfort zone. The good news is that Colorado offers quite a few rafting experiences with miles of flat water that are just right for first-timers, and this section of Clear Creek fills that bill. Just thirty miles west of Denver, the put-in at Idaho Springs for the Gold Rush segment winds through a historic mining valley for a two-and-a-half-hour float that never gets more challenging than Class III rapids, with most of the seven miles sitting solidly in the Class II range. Kids as young as six can go with the flow here, and this gentle introduction is so enjoyable that rafters of all ages will be begging for big water as soon as they hit dry land again.

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This Class IV-V ride is not for the faint of heart, as the Arkansas River turns into a bit of a beast when it hits the Royal Gorge Canyon. But for whitewater enthusiasts, it's a bucket-list must. Enjoy huge drops, long wave trains and a narrow canyon with steep walls that's completely cut off from the road. Then get ready for paddle-gripping rapids with names like Sledgehammer, Squeezebox, Wallslammer and Boateater. The Royal Gorge Route Railroad goes past twice a day, and there's a good chance you'll see bighorn sheep on the banks, all of which just adds to the dramatic scenery you're zipping past. The truly courageous should do what local outfitters refer to as the Grand Slam or the Double Dip, the heart-racing river rat's dream run through the Royal Gorge twice in one day, with lunch in the middle and a shuttle back to the beginning. Forward!

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Just a few miles from Cañon City in the Wet Mountain Valley, Grape Creek winds toward Westcliffe through Temple Canyon. Although it takes some sleuthing to locate the public-access points and a four-wheel-drive vehicle to get in there (BLM 6227 is a good bet, and you can hike in from the bridge parking just west of Cañon), it's well worth the trouble in spring, early summer and fall for serious anglers looking for gentle stair-step rapids and deep pool after deep pool of brownies, rainbow, brook and cutthroat trout. Fish tales tell of seventeen- to twenty-inchers, but the majority are in the ten- to thirteen-inch range, and because it can take some bushwhacking to get to the best spots, you're likely to be solo. When the fish aren't biting or it's time for a break, hike around the canyon for views of the Sangre de Cristo mountains and the cliffs of Scrapping Ridge.

Readers' Choice: Golden Gate Canyon State Park

Outside Canon City

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Hit this section of the South Platte River, between Spinney Mountain and Eleven Mile State Park east of Hartsel, at sunrise for the big ones: The browns, rainbows, cutthroats and cutbows are all famously "monster-size." Named for the late Denver Post outdoor columnist famous for his love of all things hunting and fishing, this section is ideal for beginners, because the high-desert prairie location means there's very little for the fly to tangle in, and the clear water makes it easy to spot your prey. The fact that the area has become so well known means you're not likely to be alone, but anglers willing to cast on windy or colder days will be rewarded with some solitude. And don't forget the waders: This Dream Stream, as it's also known, is always numbingly cold.

Readers' Choice: Steamboat Springs

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There are about a dozen Orvis authorized stores around the state offering free fly-fishing classes, but the Cherry Creek shop also has the location going for it, surrounded by good restaurants for that post-lesson discussion about which stream to head to first. And trust us, you'll be ready: The Fly-Fishing 101 class, which is offered Saturdays from 9 to 11:30 a.m. starting March 31 and running through mid-August, covers all the basics of fly-casting and outfit rigging, and anyone eight and older can participate (under sixteen, bring an adult). Once you complete the course, you get a free one-year membership to the conservationist nonprofit Trout Unlimited, as well as coupons for gear. In the winter, learn Fly-Tying 101 for free, too. Not surprisingly, these classes are popular, so reservations are a must.