Which preposition to use with jehol

by Occurrences 1%

The gossip is that the Emperor is occupying his time at Jehol by marrying a fourth wife (a rather expensive proceeding) and getting tipsy.

in Occurrences 1%

(b) The northern culture existed to the west of that culture, in the region of the present Chinese province of Shansi and in the province of Jehol in Inner Mongolia.

Which preposition to use with  jehol