There is nowhere else in the world quite like Oak Ridge, TN! Established during WWII by the Army Corps of Engineers, the so-called “Secret City” was at the center of the Manhattan Project. Today. Oak Ridge continues to pioneer state-of-the-art technology that is used all around the world. The Great Smoky Mountains National Park is America’s most visited national park, yet it still holds hidden gems most visitors miss. Leave the beaten path and discover hidden treasures.