Northeast
Booker T Washington St Park
There's a bike trail, actually a loop with two inner loops within the main loop, that is also open to hiking. Do it counterclockwise and save the latter parts of it for the nice views of Chickamauga Lake. A pleasant hiking experience near to Chattanooga, but often overlooked.
http://tnstateparks.com/assets/pdf/additional-content/park-maps/booker-t-washington_park-map.pdf
Harrison Bay St Park
The Bay Loop trail is a multi-use single track that is used by bikers, runners, and hikers, each often times with their canine companions. It's pretty much flat, almost always within a stone's throw of Chickamauga Lake, and consequently with a lot of nice lake views.
http://tnstateparks.com/parks/activities/harrison-bay-hiking
N. Chickamauga Creek
From Montlake Road, hike along the creek a ways, then climb a ways, including a set of wooden steps. Lots of remnants of the coal mining that went on here years ago. Another set of wooden steps down, a creek crossing with a cable to hold on to, then a descent back down to the creek. Finally a steep climb to the other trailhead atop the plateau. We like to do the upper part as a down-and-back-up.
http://cumberlandtrail.org/website/maps-and-guides/trail-segments/north-chickamauga/
http://www.northchick.org/adventure/trails-and-hiking/index.html
Cumberland Trail, Soddy Creek
We hike the northern part of this (Board Camp Creek we call it) fairly often. Nice deep woods and creekside hiking. The southern part we do once in a while; some nice views from that section.
http://cumberlandtrail.org/website/maps-and-guides/trail-segments/three-gorges/soddy-creek-gorge-section-1/
Cumberland Trail, Possum Creek
The southern portion of this has a couple big up-and-down's that take you through a pair of really scenic deep gorges; there are really nice bridges across Big and Little Possum Creek. There's one nice overlook from the ridge in between the gorges.
http://cumberlandtrail.org/website/maps-and-guides/trail-segments/three-gorges/possum-section/
Cumberland Trail, Rock Creek
We do an out-and-back from Retro Hughes trailhead or a one-way from there to the Upper Leggett Road trailhead. We also do a loop that includes the part down by the creek and the part up on the plateau that includes Leggett Point Overlook; we do this starting from either Upper Leggett trailhead or from Lower Leggett Road trailhead.
http://cumberlandtrail.org/website/maps-and-guides/trail-segments/three-gorges/rock-section/
Dayton Laurel/Snow Wilderness
A favorite of ours for waterfalls and views. A fairly easy hike is just to go up to the base of Laurel Falls. Good in winter and spring when the water flow is stronger. Going on up to the overlooks above requires more climbing, especially a rugged steep scramble through a notch in the bluff to get up on top; but the views from Laurel Creek and Bryan overlooks are worth it. For a longer more strenuous option we continue on upstream and cross over to climb the other side of the gorge. There we go to Snow Falls or Buzzard Point Overlook (another great view), or we do both. Reaching Snow Falls requires wading the creek just before you get to the falls, so that's not such a good option in colder weather.
(Note: As of October 2015 the first metal bridge, the one over Laurel Creek, is blocked by a large tree that fell along most of the length of the bridge. Rock stepping across the creek just downstream is possible but tricky.)
http://cumberlandtrail.org/website/maps-and-guides/trail-segments/laurel-snow/laurel-snow-sna-section/
Spring City Piney River
A big favorite in spring for wildflowers. Sometimes we hike up to Logging Camp campsite and back; sometimes we hike down from Newby Branch trailhead to Spider Den Bluff and back; and sometimes we hike all the way through with a car shuttle. Usually we do the through-hikes uphill because the views of the water seem better that way, and the climb is not really that bad. The main point of concern is the crossing of McDonald Branch; you have to step on large rocks and boulders that can be quite slippery when wet. Also, we've pretty much given up on starting from Walden Mtn Road at the Duskin Creek parking area because the road is so very rough and not often maintained.
http://cumberlandtrail.org/website/maps-and-guides/trail-segments/piney-river/
Spring City Stinging Fork Wilderness
A little gem that we probably don't visit enough. It's just a 2 mile round trip to the falls, but the falls is wonderful. The overlook, not so much.
http://cumberlandtrail.org/website/maps-and-guides/trail-segments/stinging-fork/
Spring City Black Mtn
A nice late spring wildflower hike, especially for pink and yellow Lady Slippers. A pretty good climb (we don't drive to the top, even though you can!), there are some great views to the east up on top.
Booker T Washington St Park
There's a bike trail, actually a loop with two inner loops within the main loop, that is also open to hiking. Do it counterclockwise and save the latter parts of it for the nice views of Chickamauga Lake. A pleasant hiking experience near to Chattanooga, but often overlooked.
http://tnstateparks.com/assets/pdf/additional-content/park-maps/booker-t-washington_park-map.pdf
Harrison Bay St Park
The Bay Loop trail is a multi-use single track that is used by bikers, runners, and hikers, each often times with their canine companions. It's pretty much flat, almost always within a stone's throw of Chickamauga Lake, and consequently with a lot of nice lake views.
http://tnstateparks.com/parks/activities/harrison-bay-hiking
N. Chickamauga Creek
From Montlake Road, hike along the creek a ways, then climb a ways, including a set of wooden steps. Lots of remnants of the coal mining that went on here years ago. Another set of wooden steps down, a creek crossing with a cable to hold on to, then a descent back down to the creek. Finally a steep climb to the other trailhead atop the plateau. We like to do the upper part as a down-and-back-up.
http://cumberlandtrail.org/website/maps-and-guides/trail-segments/north-chickamauga/
http://www.northchick.org/adventure/trails-and-hiking/index.html
Cumberland Trail, Soddy Creek
We hike the northern part of this (Board Camp Creek we call it) fairly often. Nice deep woods and creekside hiking. The southern part we do once in a while; some nice views from that section.
http://cumberlandtrail.org/website/maps-and-guides/trail-segments/three-gorges/soddy-creek-gorge-section-1/
Cumberland Trail, Possum Creek
The southern portion of this has a couple big up-and-down's that take you through a pair of really scenic deep gorges; there are really nice bridges across Big and Little Possum Creek. There's one nice overlook from the ridge in between the gorges.
http://cumberlandtrail.org/website/maps-and-guides/trail-segments/three-gorges/possum-section/
Cumberland Trail, Rock Creek
We do an out-and-back from Retro Hughes trailhead or a one-way from there to the Upper Leggett Road trailhead. We also do a loop that includes the part down by the creek and the part up on the plateau that includes Leggett Point Overlook; we do this starting from either Upper Leggett trailhead or from Lower Leggett Road trailhead.
http://cumberlandtrail.org/website/maps-and-guides/trail-segments/three-gorges/rock-section/
Dayton Laurel/Snow Wilderness
A favorite of ours for waterfalls and views. A fairly easy hike is just to go up to the base of Laurel Falls. Good in winter and spring when the water flow is stronger. Going on up to the overlooks above requires more climbing, especially a rugged steep scramble through a notch in the bluff to get up on top; but the views from Laurel Creek and Bryan overlooks are worth it. For a longer more strenuous option we continue on upstream and cross over to climb the other side of the gorge. There we go to Snow Falls or Buzzard Point Overlook (another great view), or we do both. Reaching Snow Falls requires wading the creek just before you get to the falls, so that's not such a good option in colder weather.
(Note: As of October 2015 the first metal bridge, the one over Laurel Creek, is blocked by a large tree that fell along most of the length of the bridge. Rock stepping across the creek just downstream is possible but tricky.)
http://cumberlandtrail.org/website/maps-and-guides/trail-segments/laurel-snow/laurel-snow-sna-section/
Spring City Piney River
A big favorite in spring for wildflowers. Sometimes we hike up to Logging Camp campsite and back; sometimes we hike down from Newby Branch trailhead to Spider Den Bluff and back; and sometimes we hike all the way through with a car shuttle. Usually we do the through-hikes uphill because the views of the water seem better that way, and the climb is not really that bad. The main point of concern is the crossing of McDonald Branch; you have to step on large rocks and boulders that can be quite slippery when wet. Also, we've pretty much given up on starting from Walden Mtn Road at the Duskin Creek parking area because the road is so very rough and not often maintained.
http://cumberlandtrail.org/website/maps-and-guides/trail-segments/piney-river/
Spring City Stinging Fork Wilderness
A little gem that we probably don't visit enough. It's just a 2 mile round trip to the falls, but the falls is wonderful. The overlook, not so much.
http://cumberlandtrail.org/website/maps-and-guides/trail-segments/stinging-fork/
Spring City Black Mtn
A nice late spring wildflower hike, especially for pink and yellow Lady Slippers. A pretty good climb (we don't drive to the top, even though you can!), there are some great views to the east up on top.