Some of the most beautiful parts of Colorado have been preserved within the federal government's national park and monument system.

Rocky Mountain National Park, easily the most popular of the state's national parks in terms of number of visitors, is also the most spectacular. Because photos of its magnificent snowcapped peaks have graced so many calendars and coffee-table books, people often envision Rocky Mountain National Park when they think of Colorado. Black Canyon of the Gunnison National Park also offers fine scenery, but it's entirely different from Rocky. Black Canyon is an extremely narrow, rocky river canyon that's wild and beautiful, but difficult to explore because of its steep canyon walls. And then there's Mesa Verde National Park; its reason for being is history, with the best-preserved ancient cliff dwellings in the Southwest.

The state's national monuments may not be as well known as Rocky Mountain National Park, but each has its own charm and is well worth a visit. For instance, Colorado National Monument is similar to the national parks of southern Utah -- somewhat barren but with marvelous red-rock formations. And Dinosaur National Monument is really two parks -- arid yet scenic canyons in Colorado and its namesake dinosaur quarry just across the border in Utah.

To get the most from your visit, try to avoid school-vacation periods and the dead of winter, when Rocky's high country and parts of Mesa Verde and Black Canyon of the Gunnison may be inaccessible. Although the parks are beautiful under a frosting of snow, you won't be able to see as much.

If you can, take a hike. Most park visitors tend to stay on the beaten track, stopping at the same scenic vistas before rushing to the next one. If you can spend even an hour or two on the trail, it's often possible to simply walk away from the crowds.

If you plan to visit a number of national parks and monuments within the time frame of a year, America the Beautiful -- National Park and Federal Recreational Lands -- Access Passes, which cost you $80 (good for 365 days from the date of purchase), will save you money. The passes are good at all properties under the jurisdiction of the National Park Service, as well as fee areas administered by the Bureau of Land Management, National Forest Service, and other federal agencies.

Saving Money with a National Parks Pass

Those who make a habit of vacationing at national parks, national forests, and other federal lands may get some use out of a new annual pass to federal lands (which, unfortunately, costs more than the old passes it's replacing). The America the Beautiful -- National Parks and Federal Recreational Lands -- Access Pass, which went on sale in 2007, costs $80 for the general public. It provides free admission for the pass holder and those in his or her vehicle to recreation sites that charge vehicle entrance fees on lands administered by the National Park Service, U.S. Forest Service, U.S. Fish and Wildlife Service, Bureau of Land Management, and Bureau of Reclamation. At areas that charge per-person fees, the passes are good for the pass holder plus 3 additional adults. Children under 16 are admitted free.

The pass, which is good for 1 year from the date of purchase, replaces the National Parks Pass, which was limited to only properties administered by the National Park Service but cost only $50, and the Golden Eagle Passport, which provided free entry to all the federal lands covered by the new pass and cost $65. The new passes are also available for U.S. citizens and permanent residents 62 and older for a lifetime fee of $10 (same as the former Golden Age passports), and are free for U.S. residents and permanent residents with permanent disabilities (also the same as the former Golden Access passports). For information or to purchase the pass, go to http://store.usgs.gov/pass or www.nps.gov/fees_passes.htm, or call the United States Geological Survey (USGS), which issues the passes, at tel. 888/275-8747. They can also be bought at park entrance stations.

Note: This information was accurate when it was published, but can change without notice. Please be sure to confirm all rates and details directly with the companies in question before planning your trip.