When to Go
Most national parks see their peak crowds in the summertime, when kids are out of school and the weather and scenery are at their best. Campgrounds, lodges and hotels fill up quickly during peak travel times, and the main roads running through the parks often get clogged with cars and RV's. You'll often have a better experience if you visit in spring or fall, when most parks are less crowded.
Does that mean you shouldn't visit during the summer? Absolutely not. While the most popular parks see millions of visitors each year, that doesn't mean you have to run into all those visitors during your trip. Crowds tend to cluster around major visitor attractions (such as Yellowstone's Old Faithful) and scenic overlooks (like those along the Grand Canyon's South Rim), but even the most popular parks have many miles of less discovered hiking trails and backcountry roads far from the tourist trail. If you can, ditch the car and take a hike to find your own little patch of natural beauty away from the crowds. Save the more popular attractions for either first thing in the morning or just before sundown in order to beat the midday rush.
Want to really avoid the crowds? Check out our favorite Less Traveled National Parks.
Planning Your Trip
Your first stop should be the Web sites of the National Park Service (for U.S. parks) or Parks Canada (for parks north of the border), both of which provide up-to-date, unbiased information about each park within their jurisdiction. These sites offer maps, trail reports, road closure information, operating hours, activity listings, fee information and much more.
AAA is also a good source for comprehensive national park maps, which members can order at no charge. If you're not a member of AAA, you can get maps at any visitor center once you arrive at the park.
Most national parks have a wide range of lodging options both within the park and outside it, ranging from campgrounds and rustic cabins to budget motels and upscale hotels. Camping is almost always your cheapest option, but keep in mind that campgrounds fill up quickly during the peak travel season. Many parks allow you to reserve your campsite ahead of time; you can do so at Recreation.gov (for U.S. parks) and PCCamping.ca (for Canadian parks).
Don't do tents? Budget travelers can stay in cabins within the park or in family-friendly motels outside the main entrances, while those willing to pay a little more can often stay in elegant lodges with beautiful scenic views. Be sure to check for the amenities that are important to you -- not all park lodging will have private bathrooms, for instance. As with campgrounds, park lodges and cabins often sell out very quickly at peak times, so be sure to book well in advance if you have your heart set on staying inside a particular park.
Slideshow: The 10 Best National Parks
If you're planning on visiting several parks over the next year, you may want to consider purchasing a park pass. The National Park Service offers the "America the Beautiful" annual pass for $80; it includes admission not only to any national park or monument but also to any sites managed by four other government agencies. The pass grants admission for the passholder and his or her vehicle (at sites that charge per vehicle) or for the passholder and up to three other adults (at sites that charge per person). Children under 16 are admitted free.
Seniors age 62 and up pay only $10 for a lifetime pass, while permanently disabled travelers can get their lifetime pass for free.
Canada also offers a variety of park passes, with packages for families and concessions for seniors and younger travelers.