To the surprise of the Mongols, the town had no fortifications whatsoever. Its citizens didn’t even intend to defend themselves and were engaged in fervent praying, asking God for their salvation. On seeing this, the Mongols rushed to the attack, but then stopped. Suddenly, they saw countless fountains of water bursting from under the ground all around them. The attackers fell back and watched the town submerge into the lake. The last thing they saw was a glaring dome of a cathedral with a cross on top of it. Soon only waves remained.
Source: Kitezh – Wikipedia
Tim B.
“This legend gave birth to numerous incredible rumors, which have survived to this day. It is said that only those who are pure in their heart and soul will find their way to Kitezh (the road to the lake is still called “Батыева тропа”, or the Path of Batu). It is also said that in calm weather one can sometimes hear the sound of chiming bells and people singing from under the waters of Lake Svetloyar. Some people[Like whom?] say that the most pious individuals may actually see the lights of religious processions (called “крестный ход”) and even buildings on the bottom of the lake.”