I just got back from Chattanooga. Now there is a city that has figured out what to do with the old downtown area. Some cities preserve it as OldTown or some such. It's been done to death! Chattanooga is home to the Tennessee Aquarium.
That has attracted resturants, museums, shops and everything tourist want. It's all located just minutes from the Chattanooga Choo Choo.

The aquarium is both fresh water and salt water. They have everything from sharks to creekchubs. A large portion is devoted to the ecology of the Tennessee Valley, but they have creatures from several continents. Easy to get to from I-75, I-24, and I-59. We took a couple of grandkids and they had a blast. (Those two have a blast every day, but this was a better blast.)
Howard