Less than 100 spots remain for the 20th Annual Mickelson Trail Trek in the Black Hills.

This is one of the most beautiful rides you'll ever encounter in South Dakota.

The South Dakota Game, Fish and Parks is encouraging bicyclists to register online at mickelsontrail.com as less than 100 spots remain for this year’s event.

The Trek will be held Sept. 15-17 and the ride is limited to 600 participants.

The annual supported ride highlights the George S. Mickelson Trail as it winds through the heart of the Black Hills, from Edgemont to Lead/Deadwood and is open to everyone 14-years-old or older.

Riders on the Trail Trek will cover the entire 109 miles of the trail over three days.