Reservoir via Grasberg and Gruener Fels to the hell holes
11.7miLength
3,136ftElevation gain
7–7.5hrEstimated time
Loop
Popular loop trail in the Swabian Alb UNESCO Biosphere Reserve, Baden-Wuerttemberg.
This loop trail on the Swabian Alb has the motto "mystical caves and striking rocks". From the Glems reservoir, you hike to the hell holes, a 100 m long demolition chasm. On the way, several imposing rock formations such as the Olgafels, the Rossfels or the Gruene Fels await you.
Highlights of the hike:
- Grasberg
- Gruener Fels
- Olgafels
- Hellholes
- Glems reservoir
- Rossberg nature reserve
- Caves on the Rossberg
This text has been translated.
Top sights
Dettinger Höllochschacht
Cave
Rossfels
Viewpoint
Olgafels
Viewpoint
Sonnenfels
Viewpoint
Grasberg
Peak
Speicherbecken Pumpspeicherwerk Glems
Reservoir
Grüner Fels
Viewpoint
Höllenlöcher
Attraction
Wiesfels
Viewpoint
Höllenlochfels
Cliff
Popular times
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Frequently asked questions
What’s helpful to know about this trail?
Experience this 11.7-mile loop trail near Metzingen, Baden-Wuerttemberg. Generally considered a challenging route, it takes an average of 6 h 40 min to complete. This is a popular trail for birding and hiking, but you can still enjoy some solitude during quieter times of day. The trail is open year-round and is beautiful to visit anytime.
What is the expected weather this week for Reservoir via Grasberg and Gruener Fels to the hell holes?
Expected weather for Reservoir via Grasberg and Gruener Fels to the hell holes for the next 5 days is:
- Fri, September 25 - 73 degrees/clear
- Sat, September 26 - 80 degrees/clear
- Sun, September 27 - 81 degrees/clear
- Mon, September 28 - 80 degrees/clear
- Tue, September 29 - 79 degrees/clear
Where is Reservoir via Grasberg and Gruener Fels to the hell holes located?
Reservoir via Grasberg and Gruener Fels to the hell holes is a trail located in Biosphärengebiet Schwäbische Alb.
How hard is Reservoir via Grasberg and Gruener Fels to the hell holes?
Reservoir via Grasberg and Gruener Fels to the hell holes is considered a hard hike that covers 11.7 mi, with an elevation gain of 3,136 ft. It takes about 7–7.5 hr to complete. Hard trails usually cover longer distances, and may have long or steep climbs or more difficult obstacles.
What is the elevation gain for Reservoir via Grasberg and Gruener Fels to the hell holes?
Reservoir via Grasberg and Gruener Fels to the hell holes is considered a hard hike that covers 11.7 mi, with an elevation gain of 3,136 ft. It takes about 7–7.5 hr to complete. Hard trails usually cover longer distances, and may have long or steep climbs or more difficult obstacles.
Is Reservoir via Grasberg and Gruener Fels to the hell holes a loop?
Reservoir via Grasberg and Gruener Fels to the hell holes is a loop trail that covers 11.7 mi, with an elevation gain of 3,136 ft. It takes about 7–7.5 hr to complete. Loop trails have the same starting point and endpoint. You'll follow a single route without retracing your steps.
How long is Reservoir via Grasberg and Gruener Fels to the hell holes?
Reservoir via Grasberg and Gruener Fels to the hell holes is a loop trail that covers 11.7 mi, with an elevation gain of 3,136 ft. It takes about 7–7.5 hr to complete. Loop trails have the same starting point and endpoint. You'll follow a single route without retracing your steps.
Are dogs allowed on Reservoir via Grasberg and Gruener Fels to the hell holes?
Dogs may be allowed on Reservoir via Grasberg and Gruener Fels to the hell holes. Be sure to check regulations before heading out.
When is the best time of year to hike Reservoir via Grasberg and Gruener Fels to the hell holes?
Reservoir via Grasberg and Gruener Fels to the hell holes is open year-round and is beautiful to visit anytime.
How busy is Reservoir via Grasberg and Gruener Fels to the hell holes?
According to trailgoers, Reservoir via Grasberg and Gruener Fels to the hell holes is usually somewhat busy. Reservoir via Grasberg and Gruener Fels to the hell holes is open year-round and is beautiful to visit anytime.
Are there scenic views at Reservoir via Grasberg and Gruener Fels to the hell holes?
Yes, according to trailgoers, Reservoir via Grasberg and Gruener Fels to the hell holes features multiple scenic viewpoints. Some of the viewpoints include Rossfels, Olgafels, Sonnenfels, Grüner Fels, and Wiesfels.
Is there birding at Reservoir via Grasberg and Gruener Fels to the hell holes?
Yes, trailgoers have said that Reservoir via Grasberg and Gruener Fels to the hell holes is good for birding. Various bird species have been spotted on the trail and in the surrounding area.
Is Reservoir via Grasberg and Gruener Fels to the hell holes paved?
Yes, according to trailgoers, Reservoir via Grasberg and Gruener Fels to the hell holes is partially paved.
Are there forests at Reservoir via Grasberg and Gruener Fels to the hell holes?
Yes, Reservoir via Grasberg and Gruener Fels to the hell holes is a forest trail in Biosphärengebiet Schwäbische Alb.
Are there wildflowers at Reservoir via Grasberg and Gruener Fels to the hell holes?
Yes, trailgoers have reported a variety of wildflower types on Reservoir via Grasberg and Gruener Fels to the hell holes, though the specific types can vary from month to month.
Is there wildlife at Reservoir via Grasberg and Gruener Fels to the hell holes?
Yes, many trailgoers have spotted wildlife at Reservoir via Grasberg and Gruener Fels to the hell holes in Biosphärengebiet Schwäbische Alb. Always observe wildlife from a safe distance.
Last updated on September 22, 2026 at 4:15 am GMT+0