What does "Advanced" grade mean for a mountain bike trail?

It means the trail falls in a steep grade band of the USFS GRADE field — steep average grades. It describes how steep the route is, not how technical it is to ride; a advanced-grade trail can still be smooth or rough depending on its surface.

How many national forest trails are Advanced grade?

About 4,887 ridable trails (19,868 mi of trail) across 25 states fall in the Advanced grade band in the current USFS data.

Is USFS grade the same as a green/blue/black difficulty rating?

No. USFS records a slope-based grade band, not the green/blue/black technical scale you see on trail-system maps. We surface the grade honestly and never infer a technical rating from it.

USFS National Forest System Trails · Grade-based steepness · Updated October 2026

Advanced Grade Mountain Bike Trails

USFS slope data places 4,887 ridable National Forest trails (19,868 mi total) in the Advanced grade band — steep average grades across 25 states. This is a steepness measure derived from the agency's GRADE field, not a technical mountain-bike difficulty rating.

Advanced-grade trails: 4,887ridable segments
Total trail: 19,868 mi
States covered: 25
Listed below: 60longest trails

Grade is steepness, not technicality. A steep grade band points to demanding climbs and faster descents, but steepness is not the same as difficulty — confirm tread, surface, and any technical features before committing to a ride here. We label these trails by the USFS GRADE field only and never translate it into a green/blue/black technical rating. Browse all ridable trails →

Longest advanced-grade trails

The 60 longest trails in this grade band, by mapped mileage. Each links to its full USFS data profile.

Trail	Miles	Surface	National forest	State
Colorado	194 mi	Native Material	Pike and San Isabel National Forests	Colorado
Continental Divide Nst	140 mi	Native Material	Rio Grande National Forest	Colorado
Rainbow	99.9 mi	Native Material	Pike and San Isabel National Forests	Colorado
Virginia Highlands	80.4 mi	Native Material	George Washington and Jefferson National Forest	Virginia
Continental Divide Nst	80.4 mi	Native Material	Salmon-Challis National Forest	Idaho
Wyoming Trail	63.5 mi	Native Material	Medicine Bow-Routt National Forest	Colorado
Highline	61.3 mi	Native Material	Caribou-Targhee National Forest	Idaho
Colorado	58.7 mi	Native Material	White River National Forest	Colorado
General Crook	57.9 mi	Native Material	Apache-Sitgreaves National Forests	Arizona
Paiute (D-1)	57.7 mi	Native Material	Fishlake National Forest	Utah
Solitude Loop	56.8 mi	Native Material	Bighorn National Forest	Wyoming
Great Western Trail, Loa	56.2 mi	Native Material	Fishlake National Forest	Utah
Alpine 7	55.3 mi	Native Material	Flathead National Forest	Montana
Cc Divide	54.8 mi	Native Material	Lolo National Forest	Montana
State Line	48.6 mi	Native Material	Idaho Panhandle National Forests	Idaho
Paiute (D-3)	47.9 mi	Native Material	Fishlake National Forest	Utah
Bears Ears	45.2 mi	Native Material	Medicine Bow-Routt National Forest	Colorado
Continental Divide Nst	45.1 mi	Native Material	Beaverhead-Deerlodge National Forest	Montana
Ranger Trail	41.6 mi	Native Material	Humboldt-Toiyabe National Forest	Nevada
Pony Express	37.9 mi	Native Material	Eldorado National Forest	California
Centennial On Northern Hills	37.5 mi	Native Material	Black Hills National Forest	South Dakota
Bt/Nct Marietta	37.1 mi	Native Material	Wayne National Forest	Ohio
Little Pend Oreille Orv	36.9 mi	Native Material	Colville National Forest	Washington
Resurrection Pass Trail	36.7 mi	Native Material	Chugach National Forest	Alaska
Shenandoah Mountain	36.1 mi	Native Material	George Washington and Jefferson National Forest	Virginia
Montana Line	36 mi	Native Material	Idaho Panhandle National Forests	Idaho
Summit	34.4 mi	Native Material	Grand Mesa, Uncompahgre and Gunnison National Forests	Colorado
Iron Mountain	34.4 mi	Native Material	George Washington and Jefferson National Forest	Virginia
Aspen Loop	33.8 mi	Native Material	San Juan National Forest	Colorado
Brookside-Mccurdy	32.5 mi	Native Material	Pike and San Isabel National Forests	Colorado
Camp 9 / Spring Gap Footbridge	32.4 mi	Native Material	Stanislaus National Forest	California
Signal Butte Multi Use	32.2 mi	Native Material	Pike and San Isabel National Forests	Colorado
Divide Nrt	31.7 mi	Native Material	Salmon-Challis National Forest	Idaho
Rim	31.3 mi	Native Material	Lincoln National Forest	New Mexico
Centennial On Mystic	31 mi	Native Material	Black Hills National Forest	South Dakota
Timberline	30.5 mi	Native Material	Grand Mesa, Uncompahgre and Gunnison National Forests	Colorado
Hay-Knapp Creek	29.8 mi	Native Material	Salmon-Challis National Forest	Idaho
Kettle Crest North	29.6 mi	Native Material	Colville National Forest	Washington
Grizzley-Helena	28.5 mi	Native Material	Medicine Bow-Routt National Forest	Colorado
Rock Creek Loop	28.4 mi	Native Material	Eldorado National Forest	California
Continental Divide	27.9 mi	Native Material	Caribou-Targhee National Forest	Idaho
Rainbow Rim	26.3 mi	Native Material	Kaibab National Forest	Arizona
Mill Creek Trail Blue Loop	26.1 mi	Native Material	Ozark-St. Francis National Forest	Arkansas
Slickrock Trail	25.9 mi	Native Material	Fishlake National Forest	Utah
Batey Bould Main Trunk	25.4 mi	Native Material	Colville National Forest	Washington
Foehl Creek	24.7 mi	Native Material	Idaho Panhandle National Forests	Idaho
Winsor	24.4 mi	Native Material	Santa Fe National Forest	New Mexico
Long Draw Ohv Loop	24.3 mi	Native Material	Apache-Sitgreaves National Forests	Arizona
Cannell Meadow	24.2 mi	Native Material	Sequoia National Forest	California
Mckenzie River Nrt	24.2 mi	Native Material	Willamette National Forest	Oregon
Great Western Ohv Alternate	23.4 mi	Native Material	Fishlake National Forest	Utah
Beale Wagon Road	23.3 mi	Native Material	Kaibab National Forest	Arizona
Lost Park Snowmobile	23.3 mi	Snow	Medicine Bow-Routt National Forest	Colorado
Boone Peak	23.3 mi	Native Material	Custer Gallatin National Forest	Montana
Doctor Park	23.3 mi	Native Material	Grand Mesa, Uncompahgre and Gunnison National Forests	Colorado
Wet Hollow - Wades Canyon	23.1 mi	Native Material	Fishlake National Forest	Utah
Inht: Johnson Pass Trail	22.9 mi	Native Material	Chugach National Forest	Alaska
Parallel	22.7 mi	Native Material	Grand Mesa, Uncompahgre and Gunnison National Forests	Colorado
Bangtail Divide	22.7 mi	Native Material	Custer Gallatin National Forest	Montana
Deerfield	22.6 mi	Native Material	Black Hills National Forest	South Dakota

Advanced-grade trails by state

How the 4,887 advanced-grade trails break down across 25 states. Open a state for its full forest-by-forest data.

State	Advanced-grade trails	Miles
Idaho	857	4,175 mi
Colorado	742	3,890 mi
California	542	1,999 mi
Utah	467	1,873 mi
Oregon	426	650 mi
Montana	362	2,182 mi
Alaska	216	511 mi
Nevada	206	383 mi
New Mexico	174	607 mi
Virginia	153	603 mi
North Carolina	153	419 mi
Washington	122	644 mi
Arizona	107	544 mi
New Hampshire	83	394 mi
South Dakota	73	254 mi
Wyoming	51	242 mi
Ohio	39	162 mi
Missouri	35	94.3 mi
Georgia	34	105 mi
Arkansas	28	94.1 mi
Vermont	8	23.9 mi
Minnesota	5	5.1 mi
Alabama	2	11.7 mi
Kentucky	1	1.6 mi
Indiana	1	1.1 mi

Frequently asked questions

What does "Advanced" grade mean for a mountain bike trail?: It means the trail falls in a steep grade band of the USFS GRADE field — steep average grades. It describes how steep the route is, not how technical it is to ride; a advanced-grade trail can still be smooth or rough depending on its surface.
How many national forest trails are Advanced grade?: About 4,887 ridable trails (19,868 mi of trail) across 25 states fall in the Advanced grade band in the current USFS data.
Is USFS grade the same as a green/blue/black difficulty rating?: No. USFS records a slope-based grade band, not the green/blue/black technical scale you see on trail-system maps. We surface the grade honestly and never infer a technical rating from it.

Other grade bands

Easy grade trails Intermediate grade trails Expert grade trails All ridable trails