nel the crest, to cut galleries in the
perpendicular walls of gorges, and to embank mountain torrents against
the spring inundation of the roadbed, where it drops to the valley
floor.

[Sidenote: Navigable river approaches to passes.]

Where gaps are low and the approaching waters are navigable, at least
for the small craft of early days, they combine to enhance the
historical importance of their routes. The Mohawk River, navigable for
the canoe of Indian and fur trader, greatly increased travel and traffic
through the Mohawk depression. The Pass of Belfort is the greatest
historic gateway of western Europe, chiefly because it unites the
channels of the Rhone, Saone and Rhine. Lake Lucerne brings the modern
tourist by boat to the foot of the railroad ascent to the St. Gotthard
Pass, as the long gorge of Lake Maggiore receives him at the southern
end. Lake Maggiore is the water outlet also of the Simplon Pass from the
upper Rhone, the Lukmanier (6288 feet or 1917 meters) from the Hither
Rhine, and the San Bernadino (6766 feet or 2063 meters) from the Hinter
Rhine.[1235] This geographical fact explains the motive of Swiss expansion
in the fifteenth century in embracing the Italian province of Ticino and
the upper end of Lake Maggiore. A significance like that of the Swiss
and Italian lakes for the Alpine passes appears emphasized in the Sogne
Fiord of Norway. This carries a marine highway a hundred miles into the
land; from its head, roads ascend to the only two dents in the mountain
wall south of the wide snowfield of the Jotun Fjeld, and they lead
thence by the valleys of Hallingdal and Valders down to the plains of
Christiania.

[Sidenote: Types of settlements in the valley approaches.]

Genuine mountain passes have only emergency inhabitants--the monks and
dogs of the hospice, the road-keepers in their refuge huts or
_cantoniere_, or the garrison of a fort guarding these important
thoroughfares. The flanking valleys of approach draw to themselves the
human life of the mountains. Their upper settlements show a certain
common physiognomy, born of their relation to the barren transit region
above, except in those few mountain districts of advanced civilization
where railroads have introduced through traffic over the barrier. At the
foot of the final ascent to the pass, where often the carriage road ends
and where mule-path or foot-trail begins, is located a settlement that
lives largely by the transmontane travel. It