American Museum of Science & Energy

To call Oak Ridge a booming town would be a literal description. Founded as a production site for the Manhattan Project atomic bomb development during World War II, Oak Ridge has a strange, controversial history as “the Atomic City.” This museum tells the tale with help from historical photographs and artifacts. Hands-on science exhibits explore robotics, static electricity and more. An exhibit dedicated to the Y-12 National Security Complex, built during WWII in Oak Ridge and still in operation today, takes a look at national defense. Earth’s energy sources, from coal to hydropower, and atomic science get explained through models, videos and other materials.

300 S. Tulane Ave., Oak Ridge, Tenn. 865-576-3200, amse.org.

Three Rivers Rambler

We may not be in the era of flying cars, but transportation surely isn’t what it used to be. Choo-choo back in time by climbing aboard a train powered by Lindy, a 1925 steam engine. The 90-minute trip begins in downtown Knoxville and travels along the Tennessee River. Keep your eyes open for quarries, scenic farmland and the Three Rivers Trestle. The latter can be found where the French Broad and Holston Rivers connect to create the Tennessee River. Special Christmas rides hit the rails during the holidays.

2560 University Commons Way, Knoxville. 865-524-9411, threeriversrambler.com.

Ripley’s Aquarium of the Smokies

Although Gatlinburg teems with touristy flash and family-friendly attractions, this aquarium swims to the top. Habitats and sections include a tropical rainforest with piranhas, a coral reef with “Finding Nemo”-esque clownfish, a shark lagoon, a penguin area and more. Watch live shows, including divers interacting with sharks, keepers feeding the African penguins and a lesson in marine science. During the summer months, keep a look out for mermaids cruising the deep. Spring for a special add-on experience to rub flippers with penguins or take a dip with stingrays in Touch-A-Ray Bay.

88 River Road, Gatlinburg, Tenn. 865-430-8808, ripleyaquariums.com/gatlinburg.