The Cathedral of Saint Peter-in-Chains is a Roman Catholic Cathedral in Peterborough, Ontario, Canada. The Cathedral is part of the Roman Catholic Diocese of Peterborough. The parish was established in 1826 to serve the large Irish population in the area. When the Diocese was established in 1882 the parish became a cathedral. The current building was built in 1837-8 in the Gothic Revival style then popular in Upper Canada; it is one of the oldest remaining Catholic Churches in Ontario. The Cathedral was built reportedly designed by architect James Chevette.