Saturday marks the start of National Park Week, and to kick it off, the National Park Service is waiving admissions fees on April 20 for parks that generally charge one.

That includes six parks in Maryland and five in Virginia. You can use the free admission day as an excuse to take a road trip through Shenandoah National Park, or pack up a beach bag for Assateague Island National Seashore.

Each day of Park Week also has a theme, from Junior Ranger Day, when kids can earn a Junior Ranger badge, to Transportation Tuesday, when visitors can learn about the history between transportation and the evolution of national parks.

The Park Service will waive fees on three other days this year: August 25, September 28, and November 11.

Here are the parks in our region that will have free admission:

Maryland

Antietam National Battlefield
Assateague Island National Seashore
Chesapeake and Ohio Canal National Historical Park
Fort McHenry National Monument and Historic Shrine
Fort Washington Park
Harpers Ferry National Historical Park

Virginia

Assateague Island National Seashore
Colonial National Historical Park
George Washington Memorial Parkway’s Great Falls Park
Prince William Forest Park
Shenandoah National Park

This story originally appeared at WAMU.