We're wrapping up our series on national parks with your experiences. Listeners from all corners of the country have texted, posted, and phoned in their favorite memories of national parks.

The current states of some national parks, despite our country's efforts to conserve them, are still threatened by climate changes. In the future, they may be radically different, especially the parks primarily composed of glaciers and snow.

Everyone has their own story to share when they come back from a National Park. When collected together, these stories create a history and a culture. Documentarian Ken Burns joins us to discuss his journey to capture the spirit and tales of the National Parks.

While the detonation of the atomic bomb in 1945 brought about death and destruction, the labs that created this bomb remain quiet and peaceful, albeit largely unseen. A bill in Congress may make these sites national parks, upping their tourism value and ensuring their preservation.

The Fourth of July sparks patriotism for many Americans, and in honor of today's holiday, what could be more patriotic than America's National Parks? Audrey Peterman is the author of "Legacy on the Land" and is a recognized National Park enthusiast.

President Teddy Roosevelt, prior to his political life, briefly led the life of a rancher. The land left a lasting impression on him, which eventually influenced his conservationist policies. Because of his efforts, national parks have become a part of the United States' identity. Today the great-grandson of President Roosevelt discusses his quest to preserve the Elkhorn Ranch, where Teddy Roosevelt had lived as a rancher.