If you're planning a spring trip to a National Park Service site, you may be able to save a little money if you schedule your visit between April 17 and 25, 2010. Free admission to all 392 NPS sites is being offered during National Park Week.

“We are rolling out the red carpet and inviting everyone to visit a national park and help celebrate National Park Week,” said Secretary of the Interior Ken Salazar. “Parks are fun and affordable destinations and great places to engage in healthy, outdoor activities, whether for a few hours or a few days.”

During the week, many parks will also offer additional family friendly activities and special offers on tours, lodging, food, and souvenirs. A listing of parks offering special promotions is available on-line.

National Park Week is an annual event, and NPS officials point out it's "an opportunity to engage families and communities in America’s Great Outdoors, reconnecting them with nature and creating close to home opportunities for people to get outside, be active, and have fun."

“National parks preserve our heritage, promote recreational experiences, and provide places of quiet refuge,” said National Park Service Director Jon Jarvis. “Most people live within a short drive of a national park so I encourage everyone to spend some time enjoying America’s Great Outdoors during National Park Week.”

One day during the week-long event will have a special emphasis: Saturday, April 24 has been designated National Junior Ranger Day. There will be special activities on that day at many sites, and each child participating in Junior Ranger activities will receive a certificate, patch, or pin. If you can't visit a park in person, but have a young person in the family who'd like to get involved in the Junior Ranger program, check out the Web Rangers program.

Several milestones will be also be observed during National Park Week, including the 40th anniversary of Earth Day and the 75th anniversary of the nation’s most visited national park, the Blue Ridge Parkway. Rainbow Bridge National Monument in Utah and Sitka National Historical Park in Alaska are among the areas celebrating a centennial this year.

Normally, 146 of 392 national parks charge entrance fees ranging from $3 to $25. The other 246 do not charge for admission. The fee free waiver for National Park Week does not include other fees collected in advance or by contractors—such as fees charged for camping, reservations and use of concessions.

If you'd like to find information about NPS sites near your home or along the route of an upcoming trip, links to individual park areas are available on the "Find a Park" page of the agency website.