The Union Church/St. Paul's Church is a historic church building at 3 Robertsville Road in the Riverton section of Barkhamsted, Connecticut. Built in 1829 to be shared by multiple congregations, it is an architecturally distinguished example of Greek Revival design with Gothic features. It became an Episcopal church in 1880 which closed in 1971, and served for a time as a local history museum. It now houses a glass-blowing studio. The building was listed on the National Register of Historic Places in 1985.