With Hurricane Irene expected to bring high winds and heavy rains to the Eastern Seaboard, officials at the Delaware Water Gap National Recreation Area have decided to shutter much of the NRA in advance of the storm.

This northern Minnesota park's waterway system, consisting of four large island-studded lakes connected by narrows, was once the route of the French-Canadian voyageurs. A large peninsula with a glaciated, boreal forest landscape completes the ensemble.

Butterflies, wildflowers and a restored piece of tallgrass prairie will be the focus of ranger guided walks at Herbert Hoover National Historic Site on Labor Day. Visitors who'd like to give a little back can help with a volunteer project in the park's 81-acre tallgrass prairie on September 24.

A closer inspection of the Washington Monument in the wake of Tuesday's earthquake has revealed cracks in the uppermost section of the monument, prompting the National Park Service to call in structural engineers with expertise in earthquake engineering to assess the damage.