Status: Unincorporated
Established: 1910

Petrolia was founded in 1910 while Allen County’s population was near its prime.  Petrolia boasted a post office, express office, and was considered a trading point for surrounding communities in Allen and Neosho Counties.  Petrolia’s largest population was near 200 residents.  In 1953 the post office closed.  Though businesses and the post office have left, Petrolia still remains a quaint bedroom community.