I personally recommend Fujinomiya trail for the first time climber. Fujinomiya trail is the shortest route to Japan's highest point, Kengamine. And you can descend back to Fujinomiya 5th station by Gotenba trail via Hoei crater. The scenery is simply amazing and you can feel the ‘volcano’ Mt. Fuji. Subashiri trail is also good, less crowded till 8th station. Subashiri trail is gentle uphill compared to Fujinomiya trail.
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