The National Park System offers countless paddling opportunities...as well as impediments to paddling. There are free-flowing, gin-clear streams, and pollution threats in the form of fracking operations, agriculture, and population growth. And there are experiences that will pull you into wilderness settings that seemingly turn the calendar back a century or more.

Traveling to a national park that may limit vehicular activity? Look for other options to combine several days' stay with photography like Rebecca Latson did during her time in Denali National Park and Preserve, Alaska.

One of the classic scenes in Yosemite National Park is found from Glacier Point, an overlook which provides outstanding views of park landmarks such as Half Dome, Yosemite Falls, Yosemite Valley. Glacier Point is an understandable favorite with park visitors, but you'd usually need cross-county skis to get there in March. That's not the case this year, and the Glacier Point Road is already open to traffic.

With the National Park Service's 100th birthday little more than a year away, the agency and the National Park Foundation are beginning to rollout the celebratory campaign, urging Americans to "Find Your Park."