-- Heavy traffic. With the development and improvement of shipbuilding technology, ships are developing towards large scale. The giant passenger ship has exceeded 80,000 tons, the supertanker has exceeded 500,000 tons, is the general general cargo ship is also more than 50,000, 60,000 tons. Therefore, sea transport has the advantage of large carrying capacity.
-- Strong ability to pass. Sea transportation is accomplished by using natural waterways. These routes connect ports all over the world. Unlike cars and trains, they are not subject to road or rail restrictions. In addition, they can always choose the most advantageous routes in case of changes in political, economic, trade and natural conditions.
-- The freight is low. Sea transport through the waterway are naturally formed, port facilities are generally built by the government, unlike road or rail transport, which requires a large investment in the construction of roads or tracks; On the other hand, compared with other modes of transport, the unit transport cost of sea transport is lower because of its large carrying capacity, long service time and long transport mileage. All these factors make sea transportation very cheap.