You come to the Gap from the south on county roads. This is a couple hour hike but to get a high view, you have to climb so the way there might take longer than you hope. The trails are easy to walk and clear.
Take Raum road South to Dutton Chapel Road East. (left) You will come to the intersection of Lusk road and take it North East. (left) It MAY or may not be in good shape. They graveled it at one time and it was decent last time I saw it a couple of years ago. It will intersect the trail you want. I’ll try and scrounge and come up with the trail number. It is just a white diamond trail and looks by the map as if it crosses the road at an intersection with an unmarked road. Some of these roads are only roads to 4 wheelers. The sure way to get there but maybe a quarter mile longer walk is from One Horse Gap Lake. (With a turn around at the lake and room for a few cars to park)
Official directions are
Travel south from Harrisburg on Illinois Route 34/145 to Mitchellsville and continue on Illinois Route 34 toward Eichorn. Just before Eichorn turn west, traveling approximately 6 miles, on Forest Service Route 126, a gravel road leading to Leisure City and across the Grand Pierre Creek to One Horse Gap.
Take the trail around the bottom of the lake to the West, Cross the gravel road and up to one horse gap. There are some nice rock bluff areas above the gap and a trail around the top of the ridge that is very beautiful, but I actually couldn’t find it the last time I was up there. My wifes feet were hurting and we gave up quickly and went back down. The overlook site is actually further North along the river to river trail. (NOT West from One Horse Gap, but back towards Herod.) It isn’t far, a half or maybe a full mile but it is pretty bluffs you are walking under and the trail is relatively level. You will get to a cross trail that is well traveled heading back East. You are only a couple hundred feet down this trail away from the overlook, and I had been there before and never noticed it through the trees!
There is a big clearing & fire ring and horse tie up area. The view is unobstructed to the North West and amazing. If you want to skip one Horse Gap, or have already been there, The white diamond trails on the map will bring you back by a very scenic route though it is fairly steep down in a couple of places. I came this route once on the last day of a 3 day hike in order to gat a ride from a friend camping at One Horse lake and it came out right at the dam on the North side of the lake where he was camping. It follows the road across the dam and brings you back to the original trail to the crossroads and back to the parking area south of the lake.
I actually can’t find a photo of one horse gap, but to tell the truth it wasn’t all that photogenic, more of a historical point than a photo op.
Evening at overlook.
Jan. 2012 trip with wife and “Little Brother”.