Palace Square. The central city square of St Petersburg and of the former Russian Empire was the setting of many events of worldwide significance, including the October Revolution of 1917. The earliest and most celebrated building on the square is the baroque white-and-azure Winter Palace of Russian tsars, which gave the square its name. The opposite, southern side of the square is occupied by the bow-shaped Empire-style Building of the General Staff which centers on a double triumphal arch crowned with a Roman quadriga. The centre of the square is marked with the Alexander Column. This red granite column (the tallest of its kind in the world) is 47,5 meters high and weighs some 500 tons. It is set so well that no attachment to the base is needed.