• 它需要足够深，以便你可以乘坐延伸到海平面以下几米的船靠近海岸。

• 它需要保护不受大浪的影响，所以围绕港口的一小片陆地是有用的。< / p >

• It shouldn't be in a place where tides are large and ships will be moving up and down over the course of a day by too much to make loading and unloading difficult.

• It shouldn't be in a place where winds are frequently too strong to make operations difficult.

The land adjacent to such maritime locations needs to be reasonably flat and cover a large area so that holding yards can be established for goods arriving and leaving via a port and to facilitate land based transport networks, such as rail and road, in moving goods to and from ports. Steep coastlines, as one finds with fjords, are sub optimal for use as ports.