Defenders at Sveaborg often fired at the Russian cossack patrols on the ice around the fortress, but without any practical results. Instead of attacking the numerically inferior besieger, the Swedes were content to stay behind their fortifications and prepare for the Russian assault by sawing a ditch to the open the ice around the fortress. The first Russian barrages were fired on 19 March and continued until 21 March, after which first attempts to negotiate were made. Cronstedt agreed not to fire at the town of Helsingfors in exchange for the Russians keeping their artillery batteries away from that direction. This suited the Russians since it allowed them to lodge their troops in Helsingfors without danger of being shot at by the Swedish artillery.