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Panama Canal
Ships traveling around the South
american coast from the Caribbean
Sea to the Pacific Ocean once had to
sail nearly 6,000 miles (10,000 km)—
until the United States built a huge
canal through Panama in Central
america where the Pacific and the
Caribbean are just 51 miles (82 km)
apart. The canal opened in 1914.lOCkS
To raise or lower ships from one water level to
another, canals and harbors have locks. If a ship is
going to a lower water level, the lock fills with water
and the ship sails in. Closing the upper gates and
letting out the water gradually lowers the ship to
the level of the water outside the lower gates.SIngaPOre
at the center of the sea routes
of southern asia lies Singapore,
one of the busiest ports in the
world. Its large, modern docks
handle goods from all over the
world. many large ships from
europe and the americas unload
their cargoes here into smaller
vessels for distribution to
nearby countries.COnTaInerS
a special wheeled
crane handles
containers. It lifts
them off the ship
and can either
stack them nearby
or lower them
on to the back of
a truck. Cranes,
ships, and trucks
around the world have the same
size fittings so that they can move
containers easily between
different countries.Ports and waterways
Lock gates can open for
the ship to sail in only
when the water on each
side is at the same level.Opening paddles, or
valves, in the sides and
gates of the lock allows
water to flow out.When all the
water has
drained from
the lock, the
gates open
and the ship
can continue
on its way.ShIPS lOad and UnlOad their cargoes at ports, or harbors—sheltered places
on coasts or rivers with cranes and warehouses to handle ships, passengers, and
goods. road and rail connections link the ports with inland areas. The earliest
ports were simply landing places at river mouths. here ships were
safe from storms, and workers on board could unload
cargo into smaller boats for transport upriver.
Building walls against the riverbanks created
wharfs to make loading easier. In the 18th and
19th centuries, port authorities added docks—
deep, artificial pools—leading off the rivers. Ships
and boats use waterways to sail to inland towns or
as shortcuts from one sea to another. Waterways
can be natural rivers or artificial rivers called
canals. One of the world’s largest
waterway systems, based on
the mississippi river, links the
great lakes with the gulf of
mexico. It includes 15,000 miles
(24,000 km) of waterways.dOCkS
huge gates at the entrance to the
docks maintain the water level
inside. The warehouses and
cranes of the old-style docks are
disappearing today as more ships
carry cargo in containers—large
steel boxes of standard size that
are easy to stack and move.Find out more
navigation
Ships and boats
Trade and industryNavigation
lights guide
ships safely
into the port.Because oil burns easily,
oil tankers use special
terminals to unload their cargo.Huge tanks at the
terminal store the oil
until it is needed.Ships and boats
unload at wharfs.lOadIng and UnlOadIng
Ships carry nearly two-thirds of all
cargo in containers, but many items do not fit
neatly inside them. Cranes lift these individual large
pieces of cargo on and off the ships. loose cargo such
as grain is sucked up by huge pumps and carried ashore
through pipes. Vehicles drive on to special ships
known as “ro-ros”: roll-on, roll-off ferries.US_419_Ports.indd 419 22/01/16 4:46 pm