HM USA Travel Guide - About National Parks

The National Park System Includes 378 areas. Among them are 55 National Parks and 72 National Monuments. In 1998 the NPS units were visited by 287 million people. The Blue Ridge parkway in Virginia attracted the most visitors: over 19 million. With 10 million visitors the most frequent visited National Park was the Great Smoky Mountains NP. Other parks that attract many visitors are The Grand Canyon (4.5 million), Yosemite NP (3.5 million) and Olympic NP (3.3 Million).
For more information see Public Use Statistics Office Home Page

Most of the national parks (and other NPS units) charge an entrance fee. The amount charged differs per park. Smaller parks may charge $5 or $10 per personal vehicle and occupants while the most popular parks charge up to US $20. The entrance permit is often valid for 3 or 7 days. If you enter the park on foot or by bike a fee per person is charged. Most parks also offer anual passes.

National Parks pass
If you are planning to visit several parks you might consider purchasing an National Parks Pass. The pass costs US $50 and is valid for one year. The pass can be purchased at any NPS unit and covers the entrance fees for most of the NPS units like national parks en monuments. However the pass is not valid for some national parks. For instance it is not valid for a vist to alcatraz Island (san Fransisco) because you have to pay for the tranportation (by boat). See also Experience Your America with the National Parks Pass

Golden Eagle pass
The National parks passpor is what used to be the Golden Eagle Pass. The Golden Eagle pass can still be purchased and it costs $ 65. This pass is not only valid for NPS areas but also for Bureau of Landmanagement areas (like national forests).

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