The Battle of Vilnius was the first time a foreign power managed to capture a group of cultural, and historic structures on the left bank of what river?
Battle of Vilnius (1655):  It was the first time that a foreign power managed to capture the Vilnius Castle Complex. Vilnius Castle Complex: The Vilnius Castle Complex (Lithuanian: "Vilniaus pilių kompleksas" or "Vilniaus pilys" ) is a group of cultural, and historic structures on the left bank of the Neris River, near its confluence with the Vilnia River, in Vilnius, Lithuania.
the Neris River