Start
OSM map layer · LineString
49.50, 3.31 · rel 14000721
49.50, 3.31 · rel 14000721
GR®12A
142,6 km from Pierrefonds to Saint-Erme through alpine terrain and lakes.
Pierrefonds
→
Saint-Erme
linear
142,6km
Distance
multi-day
Climb · estimate
moderate
Difficulty · estimate
linear
Shape
26
views
01 · Character of the route
Is this one for you?
Alpine Terrain
Lakes
Mountains
Urban Area
Summit
Castle or ruins
Remote
Uncrowded
compiled from map data (OSM) and points of interest along the route — no editorial layer
02 · 20 points along the route
What will you encounter?
7× summit
4× monument
3× Water
2× ruins
1× Windmill
1× Attraction
2× castle
Les Beaux Monts
summit ·
462 m off route
0,0 km
0%
Saint-Just
monument ·
on the route
142,6 km
100%
Fontaine Saint-Brice
Water ·
on the route
142,6 km
100%
Monument aux Morts
monument ·
on the route
142,6 km
100%
source Poittevin
Water ·
on the route
142,6 km
100%
Le Tombeau de Brunehaut
ruins ·
on the route
142,6 km
100%
Moulin de l'empereur
Windmill ·
on the route
142,6 km
100%
Fontaine Maître Jean
Water ·
47 m off route
142,6 km
100%
Mont Collet
summit ·
71 m off route
142,6 km
100%
Abbaye des Prémontrés
Attraction ·
144 m off route
142,6 km
100%
Château de Blérancourt
castle ·
148 m off route
142,6 km
100%
Borne Vauthier № 32
monument ·
153 m off route
142,6 km
100%
Ancien château de Blérancourt
castle ·
173 m off route
142,6 km
100%
Observatoire 14-18 Tracy le Mont
ruins ·
174 m off route
142,6 km
100%
Monument aux Morts
monument ·
206 m off route
142,6 km
100%
Mont Saint-Mard
summit ·
261 m off route
142,6 km
100%
Mont d'Arcy
summit ·
281 m off route
142,6 km
100%
Mont l'Ecange
summit ·
358 m off route
142,6 km
100%
Mont du Fouilleux
summit ·
430 m off route
142,6 km
100%
Mont de Choisy
summit ·
452 m off route
142,6 km
100%
03 · Landmarks
Steady waypoints
Quarter of the way
Halfway
Three quarters
Finish
04 · Intersecting routes
Where you meet other trails
05 · From the trail
Through the eyes of hikers
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06 ·
no reports yet
What hikers experienced
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07 · Before you go
Answers to common questions
GR®12A is 142.6 km long.
At an average walking pace, GR®12A takes approximately 35h 29min to complete.
No, GR®12A is a linear (point-to-point) trail. It runs from Pierrefonds to Saint-Erme. Plan ahead for return transport.
GR®12A starts at Pierrefonds.
GR®12A is a strenuous hike requiring excellent fitness and prior hiking experience.
GR®12A is maintained and managed by FFRP.
Yes, GR®12A is part of the National Walking Network (NWN), a wider network of long-distance hiking trails.