Historians point out that ideas, and the organizations associated with them, sometimes age and lose their relevance. Today, as the National Park Service (NPS) approaches the centennial of its establishment, the agency faces huge potential problems with its founding mission and subsequent land management policies.

Though it's easy to imagine the Mississippi River as a wide, barge-crowded river, there are sections that are quite tranquil and which draw paddlers, not barges. The Mississippi National River and Recreation Area protects some of those upper reaches of the Mississippi.

The birth of a chick earlier this year to a pair of nesting California condors was cause for celebration at Pinnacles National Monument, but scientists tracking the health of the young bird have bad news. Due to extremely high levels of lead in its blood, it's been necessary to evacuate the bird from its nest to a specialized facility for intensive treatment. Is lead ammunition the culprit?

The name can be a mouthful, turning your tongue in knots as you try to pronounce "Two-ahl'-oh-me." Native American in origin, some believe Tuloumne means "Many Stone Houses" or "Straight Up Steep," which, if you've ever traveled the Tioga Road through Yosemite National Park, certainly seems appropriate.