The plain lying between this coast range and the Andes dips below sea-level in the gulfs of Ancud and Corcovado (average width, 30 m.).
The northern coast range is formed by the oldest rocks in the island, consisting chiefly of limestones and marbles with occasional masses of igneous rock.
That part of California which lies to the south and east of the southern inosculation of the Coast Range and the Sierra comprises an area of fully 50,000 sq.
Lying between this coast range and the Andes is a broad valley, or plain, extending from the Aconcagua river south to the Gulf of Ancud, a distance slightly over 620 m.
The Pacific border of the coast range of British Columbia is ragged with fjords and channels, where large steamers may go 50 or Too m.
A number of small streams, among them the Nehalem, Coquille and Umpqua rivers, cut their way through the Coast Range to reach the ocean.
The Coast Range is heavily forested in the north, where rainfall is abundant in all seasons; but its lower ranges and valleys have a scanty tree growth in the south, where the rainfall is very light: here grow redwoods (Sequoia semperzirens) and live oaks (Quercus agrifolia).
North of Cape Frio the Coast Range is much broken and less elevated, while the Serra do Espinhaco takes a more inland course and is separated from the coast by great gently-sloping, semi-barren terraces.
Slope of the Olympic, Coast range and Cascade Mountains is from 60 to 120 in.
A portion of the Puget Sound Basin and a portion of the Coast range are drained by the Chehalis river, which has cut a channel through the Coast range and discharges into Gray's Harbour.