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Level: Intermediate
Length: 11 mi (17.7 km)
Surface: Singletrack
Configuration: Loop
Elevation: +610/ -487 ft
Total: 16 riders

Mountain Biking Trail 40L / Deerfield Lake Loop

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#29 of 44 mountain bike trails in South Dakota
#6,305 in the world

Follow highway 16 Mount Mushmore road out of Rapid city to Hill City.take highway 385 north out of hill city to Deerfield lake.

First added by alvin.santoy on Dec 31, 2002. Last updated May 11, 2020. → add an update
Before you go
  • Drinking water: unknown
  • Lift service: unknown
  • Night riding: unknown
  • Pump track: unknown
  • Restrooms: unknown
  • Fat bike grooming: unknown
  • E-bikes allowed: unknown
  • Fee required: unknown
This trail information is user-generated. Help improve this information by suggesting a correction.
Getting there
this is my favorite hot weather trail.Deerfield lake is located about 20 miles from Rapid City and the interstate.It is the highest lake in the hills so when the temp is scorching down on the plains you can come up here in the 80 degree air and ride the trail around the lake for a great and challenging loop.The trail runs thru a forest service campground. it is best ridden counterclock-wise from lake elevation.You are then rewarded with a long and fast downhill to a secluded beach unseable just yards away from the regular beach area.Catch a pail full of crawdads out of the clear lake and have a feast at your campsite.The trail is all singletrack and for more advanced riders.It offers some tight switchbacks to open sections leading thru high country meadows.
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Trail 40L / Deerfield Lake Loop Trail map

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Ross Lagasse (on Sep 3, 2017)
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(on May 31, 2023)
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  • stumpy14

    Fun trail with some decent climbs and descents. Trail is in rough shape and not maintained. This made for a much slower trip and some sections were near impassable

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  • Flashman

    Did this loop around the lake with my wife and dog on our mountain bikes.
    It was scenic and moderate in difficulty. I did just come from sea level so that made it more challenging. Not technical but worth it if you are in the areas.

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