A few days later , the main army under Tsar Alexei Mikhailovich arrived Arriving on the ships on the Duna River , and laid siege Besieging to Riga .

The Russian army occupied Control three camps , two on the east bank of the Duna in Riga 's suburbs , and a Corps under Ordyn-Nashokin on the west bank of the Duna , opposite the Kobrun entrenchment .

The Russian army occupied Control three camps , two on the east bank of the Duna in Riga 's suburbs , and a Corps under Ordyn-Nashokin on the west bank of the Duna , opposite the Kobrun entrenchment .