The country for a considerable distance is dotted with old forts and ruins, and the remains of extensive earthworks.  Many battles were fought here between the Chinese and the Mongols when Genghis Khan made his conquest.  For a long time the assailants were kept at bay, but one fortress after another fell into their hands, and finally the capture of the Nankow pass by Che-pee, one of Genghis Khan’s generals, laid Pekin at their mercy.

[Illustration:  NANKOW PASS.]

There is a tradition that the loss of the first line of northern forts was due to a woman.  Intelligence was transmitted in those days by means of beacon fires, and the signals were so arranged as to be rapidly flashed through the empire.  Once a lady induced the Emperor to give the signal and summon his armies to the capital.  The Mandarins assembled with their forces, but on finding they had been simply employed at the caprice of a woman, they returned angrily to their homes.  By-and-by the enemy came; the beacon fires were again lighted; but this time the Mandarins did not heed the call for assistance.

The Great Wall—­the real one—­crosses the road at Chan-kia-kow, a large and scattered town lying in a broad valley, pretty well enclosed by mountains.  The Russians call the town Kalgan (gate), but the natives never use any other than the Chinese name.  In maps made from Russian authorities, Kalgan appears, while in those taken from the Chinese, the other appellation is used.  Kalgan (I stick to the Russian term, as more easily pronounced, though less correct) is the centre of the transit trade from Pekin to Kiachta, and great quantities of tea and other goods pass through it annually.  Several Russians are established there, and the town contains a population of Chinese from various provinces of the empire, mingled with Mongols and Thibetans in fair proportion.  The religion is varied, and embraces adherents to all the branches of Chinese theology, together with Mongol lamas and a considerable sprinkling of Mahommedans.  There are temples, lamissaries, and mosques, according to the needs of the faithful; and the Russian inhabitants have a chapel of their own, and are thus able to worship according to their own faith.  The mingling of different tribes and kinds of people in a region where manners and morals are not severely strict, has produced a result calculated to puzzle the present or future ethnologist.  Many of the merchants have grown wealthy, and take life as comfortably as possible; they furnish their houses in the height of Chinese style, and some of them have even sent to Russia for the wherewith to astonish their neighbors.

The Great Wall runs along the ridge of hills in a direction nearly east and west; where it crosses the town it is kept in good repair, but elsewhere it is very much in ruins, and could offer little resistance to an enemy.  Many of the towers remain, and some of them are but little broken.  They seem to have been better constructed than the main portions of the wall, and, though useless against modern weapons, were, no doubt, of importance in the days of their erection.  The Chinese must have held the Mongol hordes in great dread, to judge by the labor expended to guard against incursions.