It is traditional to build on the riverbanks snow fortresses reinforced by two towers and with two gates. Many children gather round these fortresses and divide themselves into two groups, which are the "cavalry" and the "infantry". The "infantry" occupy the fortress and the "cavalry" prepare for the attack. At last after the sign from their commander the cavalry starts the assault of the fortress. The fight begins. The besieged bravely defend their fortress against the "cavalry" preventing them from bursting into the fortress gates and trying to beat them off with besoms and brooms. However, the attempts of the defenders become futile and the cavalry victoriously enters the gates of the fortress. Then together with the "besieged" defenders they ruin the fortress singing cheerful songs and then return home.