Sergio
Me and my wife try to ride the Mickelson Trail every year. It's a wonderful ride. We usually do it in two days and have plenty of time to stop and explore. We always ride it north to south(Deadwood to Edgemont). We are going to be riding it in a couple weekends.
Places of interest:
Moonshine Gulch in Rochford - bar/restaurant that has greasy burgers and cold beers. They also have random locals play music on Sundays.
Alpine Inn in Hill City - owned by a German lady, they have a German lunch menu that's tasty. The dinner menu is pretty simple, big or small steak. They have a huge desert menu, which is what they are known for. They are closed on Sundays.
If you have three days, I'd say ride Deadwood to Hill City day one. Stay in Hill City and spend day two riding in the area and exploring. You've got Mt Rushmore, Crazy Horse and Custer State Park not to far away. You will ride by Crazy Horse on your way to Custer.
Maybe spend night two in Custer and finish out day three to Edgemont. The ride out onto the prairie to Edgemont is one of my favorite parts of the ride.
There is lots to do and see. The ride is overall pretty easy. I'd say the toughest part is Deadwood to the Dumont Trailhead. But it's still not that bad.
This is hands down my Favorite rails-to-trail Trail.
They do require all users by a trail pass. $3 per day or $10 annually. That money goes to maintaining the trail.
October is a really great time of the year to ride the Mickelson Trail. Nice during the day, and cools off at night. Don't forget your favorite sweatshirt for the nighttime.
If you have any other questions, let me know.
Keith