The harbour, which consists of three parts, is excellent. Its entrance at Fort McHenry is a channel 600 ft. wide, with a minimum draft (1907) of 31 ft. of water. The depth is continued with an increased width for a mile and a quarter to near Fells' Point, where the width is contracted to one-fourth of a mile with a depth of 16 ft. Above this entrance it widens into an ellipse a mile long, half a mile broad and 15 ft. deep. The third or inner harbour has a depth of 14 ft. and penetrates far into the city. Vessels of the largest class can lie at the Locust Point wharves and Canton, and vessels of 4000 tons can use the inner harbour W. of the mouth of Jones's Falls. By 1905 $5,000,000 had been appropriated since the great fire for new docks. In 1908 the city ranked fourth among the Atlantic ports of the United States in the amount of its exports ($82,113,496), and fourth in the amount of its imports ($23,722,045).

That Baltimore has grown rapidly as a manufacturing city since 1880 is seen from the fact that in that year there were but 3683 manufacturing establishments, with a total annual product valued at $78,417,304, as compared with 6359 establishments (of which 2274 were under the factory system) in 1900 producing commodities valued at $161,249,240 ($135,107,626 under the factory system); in 1905 there were 2163 establishments under the factory system with a total annual product valued at $151,546,580, an increase of 12.2% in the five years. The city ranked eighth among the manufacturing centres of the United States, as regards the value of products, in the three successive censuses of 1880, 1890 and 1900. In 1905 it was ninth. Baltimore is noted particularly as the most important centre in the United States of the canning and preserving industry. The output in 1905 ($5,981,541) of the city's establishments for the canning and preserving of fruits and vegetables was 7.7% of that of the whole United States; in 1900 it had been 15% of the country's total.

What seems to have been the first oyster-canning establishment in America was built in Baltimore (by a Thomas Kensett) in 1820, and oyster-canning as a distinct industry on a permanent footing was begun here in 1850. The term "cove oysters," now applied to canned oysters everywhere, was originally applied to the oysters found in the coves on the W. side of the Chesapeake Bay, above the mouth of the Potomac. Up to 1900, after which year oyster canneries began to be built in the southern states, especially in Mississippi, Baltimore was the centre of the oyster-canning industry. Baltimore is also a well-known centre for the manufacture of clothing, in which in 1905 ($22,684,656) it ranked fourth among the cities of the United States; for cigar and cigarette-making (1905, $4,360,366); for the manufacture of foundry and machine shop products (1905, $6,572,925), of tinware (1905, $5,705,980), of shirts (1905, $5,710,783), of cotton-duck (the output of sail-duck being about three-fourths of the total for the United States), bricks (about 150,000,000 annually), and fertilizers; it also manufactures furniture, malt liquors, and confectionery, and many other commodities in smaller amounts. The markets, especially the Lexington market, are noted for the abundance and great variety of their produce.

The proximity of coal-mines, the abundance and variety of food supplies furnished by the state, the great quantity and variety of the city's manufactured goods, the excellent shipping facilities, and the consequent low cost of living, are prominent features of the physical life of the city.