Grindstone by UTMB - 100 Mile

Grindstone 100M Aid Station Planner

All 17 Grindstone 100M checkpoints pre-loaded. Enter your goal finish time to get estimated arrival times at every aid station.

167.4km6,400m D+17 checkpointsCutoff: 36h

Full Grindstone by UTMB - 100 Mile course data: aid stations, cutoffs, course profile

Enter a goal Grindstone 100M finish time and get estimated arrival times at every checkpoint - 167.4 km with around 6,400 m of climbing, with crew and drop-bag points flagged.

Goal finish time (hh:mm)

Starting estimate based on the cutoff, not on published finish times. Replace it with your own goal.

Start time

Turns every arrival into a clock time and every cutoff into a margin.

Terrain type

Terrain changes how the goal time is shared between segments, not the total. One surface everywhere cancels out.

Checkpoints (17)

Name

Distance (km)

Cumul. D+ (m)

Cumul. D- (m)

Name

Terrain to here

Distance (km)

Cumul. D+ (m)

Cumul. D- (m)

Name

Terrain to here

Distance (km)

Cumul. D+ (m)

Cumul. D- (m)

Cutoff Fri 21:30

Name

Terrain to here

Distance (km)

Cumul. D+ (m)

Cumul. D- (m)

Cutoff Sat 00:30

Name

Terrain to here

Distance (km)

Cumul. D+ (m)

Cumul. D- (m)

Name

Terrain to here

Distance (km)

Cumul. D+ (m)

Cumul. D- (m)

Cutoff Sat 04:00

Name

Terrain to here

Distance (km)

Cumul. D+ (m)

Cumul. D- (m)

Name

Terrain to here

Distance (km)

Cumul. D+ (m)

Cumul. D- (m)

Cutoff Sat 09:00

Name

Terrain to here

Distance (km)

Cumul. D+ (m)

Cumul. D- (m)

Cutoff Sat 11:00

Name

Terrain to here

Distance (km)

Cumul. D+ (m)

Cumul. D- (m)

Name

Terrain to here

Distance (km)

Cumul. D+ (m)

Cumul. D- (m)

Cutoff Sat 15:30

Name

Terrain to here

Distance (km)

Cumul. D+ (m)

Cumul. D- (m)

Cutoff Sat 18:00

Name

Terrain to here

Distance (km)

Cumul. D+ (m)

Cumul. D- (m)

Cutoff Sat 20:00

Name

Terrain to here

Distance (km)

Cumul. D+ (m)

Cumul. D- (m)

Cutoff Sat 21:30

Name

Terrain to here

Distance (km)

Cumul. D+ (m)

Cumul. D- (m)

Cutoff Sun 01:45

Name

Terrain to here

Distance (km)

Cumul. D+ (m)

Cumul. D- (m)

Name

Terrain to here

Distance (km)

Cumul. D+ (m)

Cumul. D- (m)

Cutoff Sun 06:00

Crew may meet you at

North River Gap 1 52.1 km, by Sat 03:19
Dowells Draft 1 73.4 km, by Sat 07:10
Dowells Draft 2 115.7 km, by Sat 15:37
Camp Todd 132.1 km, by Sat 18:11
North River Gap 2 147.7 km, by Sat 21:33

Drop bags

North River Gap 1 52.1 km, by Sat 03:19
Dowells Draft 1 73.4 km, by Sat 07:10
Dowells Draft 2 115.7 km, by Sat 15:37
Camp Todd 132.1 km, by Sat 18:11
North River Gap 2 147.7 km, by Sat 21:33

Estimated arrival, cutoff margin and latest safe departure per checkpoint.
Checkpoint	Dist (km)	D+ (m)	Km-effort	Arrive by	Clock	Cutoff	Buffer	Leave by	Seg time	Seg pace/km
Start	0	0	-	0:00:00	Fri 18:00	-	-	-	-	-
Lick Run 1	9.2	+230	12.0	1:23:38	Fri 19:23	-	-	Fri 19:55Set by Wolf Ridge	1:23:38	9:05
Wolf Ridge	18.3	+300	13.5	2:57:44	Fri 20:57	Fri 21:30	32 min	Fri 21:38Set by Reddish Knob	1:34:06	10:20
Reddish Knob	32.8	+920	24.6	5:49:12	Fri 23:49	Sat 00:30	41 min	Sat 00:30Set by North River Gap 1	2:51:28	11:50
Little Bald Knob	39.3	+150	9.1	6:52:17	Sat 00:52	-	-	Sat 01:33Set by North River Gap 1	1:03:05	9:42
North River Gap 1	52.1	+320	21.1	9:19:00	Sat 03:19	Sat 04:00	41 min	Sat 04:46Set by Dry Branch Gap 1	2:26:43	11:28
Lookout Mountain	61.3	+480	15.1	11:04:15	Sat 05:04	-	-	Sat 06:31Set by Dry Branch Gap 1	1:45:15	11:26
Dowells Draft 1	73.4	+340	18.1	13:10:04	Sat 07:10	Sat 09:00	1h50	Sat 08:37Set by Dry Branch Gap 1	2:05:49	10:24
Dry Branch Gap 1likely hiking (pace)	84.7	+670	20.4	15:32:36	Sat 09:32	Sat 11:00	1h27	Sat 11:41Set by Dry Branch Gap 2	2:22:32	12:37
Cold Springslikely hiking (pace)	95.6	+620	20.6	17:56:32	Sat 11:56	-	-	Sat 14:04Set by Dry Branch Gap 2	2:23:56	13:12
Dry Branch Gap 2	104.4	+240	12.2	19:21:34	Sat 13:21	Sat 15:30	2h08	Sat 15:44Set by Dowells Draft 2	1:25:02	9:40
Dowells Draft 2	115.7	+490	19.4	21:37:08	Sat 15:37	Sat 18:00	2h23	Sat 18:29Set by Magic Moss	2:15:34	11:60
Magic Moss	124.1	+340	13.0	23:07:45	Sat 17:07	Sat 20:00	2h52	Sat 20:26Set by Camp Todd	1:30:37	10:47
Camp Todd	132.1	+80	9.2	24:11:32	Sat 18:11	Sat 21:30	3h18	Sat 22:22Set by North River Gap 2	1:03:47	7:58
North River Gap 2likely hiking (pace)	147.7	+820	29.0	27:33:40	Sat 21:33	Sun 01:45	4h11	Sun 02:57Set by Natural Chimneys (Finish)	3:22:08	12:57
Lick Run 2	160.1	+350	17.5	29:35:17	Sat 23:35	-	-	Sun 04:59Set by Natural Chimneys (Finish)	2:01:38	9:49
Natural Chimneys (Finish)	167.4	+50	8.7	30:36:00	Sun 00:36	Sun 06:00	5h24	-	1:00:43	8:19

Lick Run 1
Fri 19:23
Leave by Fri 19:55Set by Wolf Ridge
Dist (km)
9.2
D+ (m)
+230
Seg time
1:23:38
Seg pace/km
9:05
Wolf Ridge
Fri 20:57
Cutoff Fri 21:3032 minTight
Leave by Fri 21:38Set by Reddish Knob
Dist (km)
18.3
D+ (m)
+300
Seg time
1:34:06
Seg pace/km
10:20
Reddish Knob
Fri 23:49
Cutoff Sat 00:3041 minTight
Leave by Sat 00:30Set by North River Gap 1
Dist (km)
32.8
D+ (m)
+920
Seg time
2:51:28
Seg pace/km
11:50
Little Bald Knob
Sat 00:52
Leave by Sat 01:33Set by North River Gap 1
Dist (km)
39.3
D+ (m)
+150
Seg time
1:03:05
Seg pace/km
9:42
North River Gap 1
Sat 03:19
Cutoff Sat 04:0041 minTight
Leave by Sat 04:46Set by Dry Branch Gap 1
Dist (km)
52.1
D+ (m)
+320
Seg time
2:26:43
Seg pace/km
11:28
Lookout Mountain
Sat 05:04
Leave by Sat 06:31Set by Dry Branch Gap 1
Dist (km)
61.3
D+ (m)
+480
Seg time
1:45:15
Seg pace/km
11:26
Dowells Draft 1
Sat 07:10
Cutoff Sat 09:001h50
Leave by Sat 08:37Set by Dry Branch Gap 1
Dist (km)
73.4
D+ (m)
+340
Seg time
2:05:49
Seg pace/km
10:24
Dry Branch Gap 1likely hiking (pace)
Sat 09:32
Cutoff Sat 11:001h27Tight
Leave by Sat 11:41Set by Dry Branch Gap 2
Dist (km)
84.7
D+ (m)
+670
Seg time
2:22:32
Seg pace/km
12:37
Cold Springslikely hiking (pace)
Sat 11:56
Leave by Sat 14:04Set by Dry Branch Gap 2
Dist (km)
95.6
D+ (m)
+620
Seg time
2:23:56
Seg pace/km
13:12
Dry Branch Gap 2
Sat 13:21
Cutoff Sat 15:302h08Tight
Leave by Sat 15:44Set by Dowells Draft 2
Dist (km)
104.4
D+ (m)
+240
Seg time
1:25:02
Seg pace/km
9:40
Dowells Draft 2
Sat 15:37
Cutoff Sat 18:002h23Tight
Leave by Sat 18:29Set by Magic Moss
Dist (km)
115.7
D+ (m)
+490
Seg time
2:15:34
Seg pace/km
11:60
Magic Moss
Sat 17:07
Cutoff Sat 20:002h52
Leave by Sat 20:26Set by Camp Todd
Dist (km)
124.1
D+ (m)
+340
Seg time
1:30:37
Seg pace/km
10:47
Camp Todd
Sat 18:11
Cutoff Sat 21:303h18
Leave by Sat 22:22Set by North River Gap 2
Dist (km)
132.1
D+ (m)
+80
Seg time
1:03:47
Seg pace/km
7:58
North River Gap 2likely hiking (pace)
Sat 21:33
Cutoff Sun 01:454h11
Leave by Sun 02:57Set by Natural Chimneys (Finish)
Dist (km)
147.7
D+ (m)
+820
Seg time
3:22:08
Seg pace/km
12:57
Lick Run 2
Sat 23:35
Leave by Sun 04:59Set by Natural Chimneys (Finish)
Dist (km)
160.1
D+ (m)
+350
Seg time
2:01:38
Seg pace/km
9:49
Natural Chimneys (Finish)
Sun 00:36
Cutoff Sun 06:005h24
Dist (km)
167.4
D+ (m)
+50
Seg time
1:00:43
Seg pace/km
8:19

Highlighted rows use a pace heuristic (>12 min/km / >19 min/mi) - likely hiking by speed, not grade. The grade-based power-hike cue is ≥15% (see GAP and Incline tools). Times are distributed proportionally by km-effort.

Leave by is the latest you can start the next segment and still make every cutoff ahead of you at this pace - often set by a station further on, not this one. It does not yet subtract the time you spend stopped, so treat it as the optimistic edge.

Cutoff buffers are estimates from your goal time and published barriers. Courses and barriers change - verify against the official race guide.

Next step

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Grindstone 100M course in numbers

Climbing per km: 38 m
ITRA km-effort: 231 (100M)
Highest point: 1,323 m
Biggest climb: +758 m over 13.6 km at 4.1% (through Lookout Mountain)
Steepest climb: +538 m over 5.5 km at 9.5%
Longest descent: -434 m over 11.6 km at 2.8% (down to Natural Chimneys (Finish))
Track climbing above 3%: 36%
Winning time / cutoff: 21h48 / 36h00 (1.7x the winner's time)

Section-by-section climbs, descents and grades are on the Grindstone 100M course page.

About Grindstone by UTMB - 100 Mile

Grindstone by UTMB - 100 Mile covers 167.4 km (about 104 miles) with around 6,400 m of elevation gain, starting in Natural Chimneys Park, Virginia, USA. The overall cutoff is 36 hours.

Crew access is allowed at North River Gap 1 (52.1 km), Dowells Draft 1 (73.4 km), Dowells Draft 2 (115.7 km), Camp Todd (132.1 km) and North River Gap 2 (147.7 km). Drop bags are available at North River Gap 1, Dowells Draft 1, Dowells Draft 2, Camp Todd and North River Gap 2.

Checkpoint data approximate - verify against the current official race guide at grindstone.utmb.world before your race.

How the splits are allocated

Your goal time is split across the Grindstone 100M legs by km-effort: distance + gain/100 + loss/200. Full methodology.

Track your Grindstone 100M plan, crew notes, and live progress in the app

TrailMath uses these models to build periodized plans adjusted to your goals and terrain.

Start free

Checkpoints (17)

Lick Run 1

Wolf Ridge

Reddish Knob

Little Bald Knob

North River Gap 1

Lookout Mountain

Dowells Draft 1

Dry Branch Gap 1likely hiking (pace)

Cold Springslikely hiking (pace)

Dry Branch Gap 2

Dowells Draft 2

Magic Moss

Camp Todd

North River Gap 2likely hiking (pace)

Lick Run 2

Natural Chimneys (Finish)

Grindstone 100M course in numbers

About Grindstone by UTMB - 100 Mile

How the splits are allocated

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