The northern frontier is crossed by the railway from Turin to Ventimiglia by the Col di Tenda, the Mont Cenis line from Turin to Modane (the tunnel is 7 m.
The Cevennes, the Jura, the hills of central Germany, the Carpathians, the Apennines), which ar really independent ranges rather than offshoots of the main chain, the best limits are on the west (strictly speaking south), the Col d'Altare or di Cadibona (1624 ft.), leading from Turin to Savona and Genoa, and on the east the line of the railway over the Semmering Pass (3215 ft.) from Vienna to Marburg in the Mur valley, and on by Laibach to Trieste.
But really this stream is surpassed both in volume and length of course by two others which it joins beneath Briancon: - the Clairee, flowing in from the north, through the smiling Nevache glen, at the head of which, not far from the foot of the Mont Thabor (10,440 ft.), it rises in some small lakes, on the east side of the Col des Rochilles; and the Guisane (flowing in from the northwest and rising near the Col du Lautaret, 6808 ft.).
Col d'Arsine (La Grave to Monestier), bridle path Col des Pres Nouveaux (Le Freney to St Jean d'Arves), bridle path 7,523 Col des Sept Laux (Allevard to Bourg d'Oisans), bridle path 7,166 Col du Lautaret (Briancon to Bourg d'Oisans), carriage road 6,808 Col de la Croix de Fer (Bourg d'Oisans to St Jean d'Arves), carriage road..
Goldsmid, K.C.S.I., who conducted the first Seistan demarcation commission in 1872, was left undone and completed only in1903-1905by Col Sir Henry McMahon, K.C.I.E.
Of the town the Bied plunged into a deep chasm, on the steep rock face of which were formerly the subterranean mills of the Col des Roches, situated one above another; but the stream is now diverted by the above-mentioned tunnel, while another serves the railway line from Le Locle to Morteau in France (8 m.).
But what properly forms the western bit of the Alps runs, from near Turin to the Col de Tenda, in a southerly direction, then bending eastwards to the Col d'Altare that divides it from the Apennines.
In height, extends, under the name of the mountains of Charolais, Beaujolais and Lyonnais, from the Col de Longpendu (west of Chalon-sur-Saone) in a southerly direction to the Col de Gier.
In 1793 he distinguished himself by the brilliant defence of a redoubt at the Col di Tenda, with only thirty men against a battalion of the enemy.
Among the other routes may be mentioned those from Grenoble by Le Sappey, or by the Col de la Charmette, or from Chambery by the Col de Couz and the village of Les Echelles.