Among the national parks’ most valuable services are their highly informative, free ranger programs ★★★: At practically every park, rangers lead hikes, tell stories around the campfire, help you gaze into the heavens, and educate you on the area’s natural wonders and human history. Do all you can to catch at least one. Programs run all year, but the most options are found from late May to early September. Check or the park newspaper for places and times. You’re also likely to run into a roving ranger happy to answer your questions on geyser basin boardwalks or popular hiking trails. Just keep an eye peeled for the signature wide-brimmed hat bobbing among the crowds.

You can learn enough for an honorary degree in geyserology on one of the many guided walks through the Old Faithful, Norris, Mud Volcano, West Thumb, and Mammoth areas, where rangers will teach you all about the basins’ hydrothermal features. Brush up on basic wildlife safety at talks in several locations, or focus on history at Canyon and Mammoth. Guided hikes are great for anyone concerned about exploring on their own in bear country, and rangers might take you along the Grand Canyon of the Yellowstone’s rim, to Harlequin Lake, or out to see Mystic Falls. 

Yellowstone offers several fantastic after-dark talks, too. Evening programs at almost every campground or developed area cover topics from biology and geology to human history. And Madison is the place for stargazing during one of several astronomy programs held in conjunction with the Museum of the Rockies. Rangers point out constellations, watch for shooting stars, and let visitors peer into the heavens with powerful telescopes. Programs are usually held on select Friday and Saturday nights in June and July. 

If you have kids (or remain a kid at heart), you won’t want to miss the Junior Ranger Program. Pick up a $3 workbook at any visitor center and complete the activities inside—they often include attending a ranger program and going on a hike—then demonstrate your newfound knowledge with a ranger to earn a special patch and sticker. The similar Young Scientist Program for kids ages 5 and up guides participants to solve science mysteries through investigating visitor center exhibits and trails. Find a $5, self-guiding booklet at Canyon or Old Faithful Visitor Education Centers.

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.