European walking route E4

The E4 European long distance path or E4 path is one of the European long-distance paths. Starting at its westernmost point in Portugal it continues through Spain, France, Switzerland, Germany, Austria, Hungary, Romania, Bulgaria and Greece to end in Cyprus. It also visits the Greek island of Crete

Its length is more than 10,000 km, but the route through Romania and part of Bulgaria is not yet completely defined.

From: Tarifa, southernmost point of mainland Spain
through mountains of Andalucia, Murcia and Valencia via Ronda, Alhama de Granada, Moratalla, Alcoi, Requena, Morella (GR7)
2300 km
Puigcerda in Pyrenees E of Andorra
Catalan coast at Ulldecona (GR8), Tarragona via Catalan coast path (GR92), Montserrat (GR172), then GR4 into Pyrenees
450 km

Montagne Noire Via Mont Canigou and Carcassonne (GR 36),
Villefort through Haut Languedoc and Cévennes (GR 71, GR 7, GR 72),
Ardèche and Rhône valleys east via GR 44, GR 4, GR 42, 429, Swiss border near Geneva
N through Vercors, Grenoble, Chartreuse and Culoz (GR 9)
1100 km

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Wikipedia