The Grande Traversée du Jura à VTT, often shortened to GTJ VTT, crosses the Jura Mountains from Mandeure in Doubs to Culoz in Ain. The Grandes Traversées du Jura association presents it as a journey through changing mountain landscapes, with a brief Swiss section near the Doubs gorges and a choice of routes towards the southern end.
From Mandeure into the Doubs valley
Mandeure, south of Montbéliard, is the northern end of the crossing and has remains of a Gallo-Roman theatre. The route heads towards Saint-Hippolyte, at the meeting of the Doubs and Dessoubre rivers, before continuing towards Goumois and the Doubs gorges.
The river is a recurring companion in this first part of the trip. Near Goumois, France Vélo Tourisme describes a section across the Swiss border; its account of the gorges includes the Échelles de la Mort, where riders should get off their bikes. Further along, viewpoints look over the valley and the Saut du Doubs.
Forests, lakes and the Hautes Combes
The character of the crossing changes as it moves through the uplands. Explore Doubs describes a succession of valleys, forests and pastures, followed by the Mont d’Or area, the lake at Chapelle-des-Bois and the high forest of the Risoux.
Beyond the lakes of Les Mortes and Bellefontaine, the GTJ association describes the lively resort of Les Rousses and the quieter Hautes Combes. Meadows interspersed with woodland and forests of spruce and fir make this a distinctive part of the journey. The association also reminds visitors that this is habitat for sensitive wildlife, including capercaillie and Eurasian lynx.
At La Pesse, the crossing approaches the end of the Jura department. The Borne au Lion offers a view towards the Jura peaks and Crêt de Chalam before the itinerary continues into Ain.
Choosing the southern finish
From Giron, the mountain-bike and gravel itineraries separate before meeting again at Saint-Germain-de-Joux and climbing towards the Retord plateau. The association offers two options for the end of the mountain-bike journey to Culoz.
The route via La Praille explores the Valromey area. The alternative goes through Arvière and over the Grand Colombier, and the association presents it as the more demanding choice for experienced mountain bikers. Check which finish suits your group when planning the final part of the trip.
Preparing for the crossing
The GTJ association says the mountain-bike route is waymarked in both directions. Some stretches are relatively smooth, but others are rough, technical or slippery; it says a mountain bike is necessary. Its guide also describes GTJ Light alternatives intended to bypass some of the roughest, most technical or steep sections.
This is a shared landscape used by walkers and maintained by farmers. Ride in control, use the provided bike passages and respect signs and other users. Explore Doubs also asks visitors to stay on marked trails and respect quiet areas for wildlife, where local rules may apply.
For planning, the association provides a route guide and information about services along the way. France Vélo Tourisme lists accommodation and suggests sections, making it possible to organise a shorter trip as well as the full crossing.