Dubingiai Castle was a residential castle in Dubingiai, Molėtai district, Lithuania.
The first masonry castle was constructed by Vytautas, Grand Duke of Lithuania, in 1412-1413 on an island, now a peninsula, in Lake Asveja in order to secure the capital Vilnius from attacks from Livonia. No accounts concerning the architecture of Vytautas' castle have survived. It was acquired by Jerzy Radziwiłł prior to 1508.
Wikipedia https://en.wikipedia.org/wiki/Dubingiai_Castle
Coordinates 55°3'31.347" N 25°26'45.904" E