The action on Lake Peipus of 7 August 1703 was the second of three small boat actions that ended with the Russians in total control of the lake (Great Northern War). Lake Peipus lies on the border between Estonia and Russia and at the start of the Great Northern War formed part of the border between Russian and Sweden. On 7 August 1703 a Swedish fleet of thirteen small ships defeated a fleet of Russian boats, sinking twenty of the even smaller Russian vessels. After their defeat on 7 August the Russians retreated to Pskov to the south east of the lake. The Swedes maintained control of the lake for the rest of the year, before losing it in a third battle in 1704.