Bellegarde is located at the confluence of the
Valserine and the
Rhône. At this spot, the water of the two rivers runs underground; it was possible to cross both of them easily. Since the inception of the
Génissiat Dam at
Injoux-Génissiat, the level of the Rhône was raised several metres and the
Perte du Rhône submerged. A smaller, similar feature, the Pertes de la Valserine, on the former border with
Lancrans, is still visible. Bellegarde lies in a valley dominated by the Plateau of Retord on the west and the massif of the Grand Crêt d'Eau and the Vuache on the east. The passage created by the Rhône is the principal access to the area around
Gex and the north of
Lake Geneva. Since 1 January 2019, Bellegarde belongs to a new commune, with
Lancrans and
Châtillon-en-Michaille, named
Valserhône.
Climate Bellegarde is under the influence of both an
oceanic climate (notable precipitations in quantity and frequency) and a
warm-summer humid continental climate (cold winters and warm to hot summers). {{Weather box ==Transport==