Smith Mountain Fire Tower Trail has to be one of the best "bang for buck" trails we frequent. Located in Dadeville, AL on Lake Martin, the fire tower trail is only 1 mile long but worth the drive. The views from the top of the tower are spectacular to say the least. Its easy enough that a 4 year old can do it with some hand holding. There are other trails that branch off from the trailhead so you can choose your own adventure. Another favorite, when they drop the lake levels low in winter, is the Island Hop Trail. This one takes you down off the mountain to get some great close up water views of the lake. If you are looking to get your chalk bags out and do some bouldering there are a few formations where you can do just that. There are also some rope climbing spots too! More info on those below.
More info on these trails here.
https://crata.org/smith-mountain/
https://www.mountainproject.com/area/109961363/smith-mountain
If you are coming from the interstate and are hungry The Waverly Local has some of the best grub around.