Sviyazhsk is a 3.25 ha (8.0 acres) rural locality and center of Sviyazhsky Kanton that was founded in 1551 in Russia and is the site of the Assumption Cathedral and Monastery of the town-island of Sviyazhsk, which was added in the UNESCO World Heritage Site in 2017.
Sviyazhsk (Russian: ; Tatar: ) is a rural locality (a selo) in the Republic of Tatarstan, Russia, located at the confluence of the Volga and Sviyaga Rivers. 3.25 ha (8.0 acres) In 2017 the Assumption Cathedral and Monastery were added to the list of UNESCO World Heritage Sites. Sviyazhsk was founded in 1551 as a fortress, which was built within four weeks from parts made in Uglich and transported down the Volga. In 19201927, it was a center of Sviyazhsky Kanton; in 19271931the administrative center of Sviyazhsky District. It is often referred to as an island since the construction of the Kuybyshev Reservoir downstream at Tolyatti, in 1955, but it is in fact connected to the mainland by a causeway. 
