Massif

The rocky massif located around the Iset River also served as a natural fortification.

This is itself a cheerless spot, particularly on a rainy day, when, overshadowed by the great massif of rock that towers in the background, and surrounded by the grey and cheerless quarries, it has a depressing character much in contrast with the green verdure encountered on the northern end of this interesting branch line.

The southern borders of these states are keyed to the same horizontal projection, one surveyed by the frontier planter William Byrd in 1728, while the rivers forming their northern extents fall back just opposite each other from the flanks of the Appalachian massif.

Some deposits of iron ore are scattered along the edges of the massif in south - central France.

The southern portion of the zone from the Maritime Alps to the Pelvoux massif is complicated by the movements which have accompanied the formation of the mountains of Provence.