St. John's Abbey in the Thurtal, Benedictine monastery in Wildhaus-Alt St. Johann, Switzerland

St. John's Abbey is a Benedictine monastery in the Thurtal valley, set among Alpine mountains with stone buildings and a parish church. The complex shows how religious communities organized their living and working spaces during the medieval period.

The monastery was founded in the mid-12th century and received papal protection in 1152 under Pope Eugene III. A major fire in 1626 forced the monastic community to relocate, eventually establishing what became Neu St. Johann.

The monastery's name survives in two villages: Alt St. Johann marks the original site, while Neu St. Johann near Nesslau recalls the 1626 move down the valley. The former monastic church became the Roman Catholic parish church of Neu St. Johann, and the remaining buildings now house the Johanneum, a remedial educational centre.

The former abbey site lies in Alt St. Johann in the Thurtal, about ten kilometres up the valley from Nesslau and Neu St. Johann. The old monastic buildings now hold the Roman Catholic parish church and the Propsteigebäude, so visits focus on the church and the exterior; the Johanneum remedial education centre occupies the later buildings at Neu St. Johann.

The monastery's architecture still bears traces from different eras, making its long history visually apparent. Those who look carefully can see the changes between medieval and later building phases.