CRONSTADT, a strongly fortified seaport, about 20 m. w. of St. Petersburg, on a narrow calcareous island of about 5 m. in length, at the narrowest part of the Gulf of Finland, and over against the mouth of the Neva. Lat. (of cathedral) 59' 59' 46' n., long. 29° 46' 38' east. C. is at once the greatest naval station and the most flourishing commercial port of Russia. It was founded by Peter the great in 1710, the island having been taken from the Swedes by him in 1703. Its fortifications, which protect the approach to St. Petersburg, have been an object of great attention to the Russian gov ernment. The batteries are very numerous, defending every part of the channel by which vessels can enter. They are built of granite, and armed with the heaviest ord nance. The place, indeed, was considered by the British admiral who reconnoitered it during the Russian war of 1854-55, so impregnable that it would have been utter madness to make any attempt upon it. C., which is the seat of the Russian admiralty,
has three harbors: the east, mtendcd for vessels of war, and capable of accommodating 30 ships of the line; the middle harbor, where vessels are fitted up and repaired, and which is connected with the former by a broad canal; and the west or merchant's harbor, for the merchant with capacity for 1000 vessels; all are admirably defended. Not only the trade of St. Petersburg is conducted through this port. but that of a great part of the interior of Russia, which is connected with it by navigable rivers and canals. C. contains many well-built houses; the population in summer amounts, with the gar rison of about 20,000 men, to 45,000 or 50,000; in winter it is much less.