Which preposition to use with chambersburg

at Occurrences 1%

I entered Chambersburg at 6 P.M....

on Occurrences 1%

Lee, in personal command of the corps of Hill and Longstreet, had meanwhile moved on steadily in the direction of the Susquehanna, and, reaching Chambersburg on the 27th of June, "made preparations to advance upon Harrisburg.

without Occurrences 1%

No officer or soldier under the rank of a general is allowed in Chambersburg without a special order from General Lee, which he is very chary of giving, and I hear of officers of rank being refused this pass....

Which preposition to use with  chambersburg