The island of the Utopians is two hundred miles across in the middle part, where it is widest, and nowhere much narrower than this except towards the two ends, where it gradually tapers. These ends, curved round as if completing a circle five hundred miles in circumference, make the island crescent-shaped, like a new moon. Between the horns of the crescent, which are about eleven miles apart, the sea enters and spreads into a broad bay. Being sheltered from the wind by the surrounding land, the bay is not rough, but placid and smooth instead, like a big lake. Thus nearly the whole inner coast is one great harbour, across which ships pass in every direction, to the great advantage of the people. What with shallows on one side and rocks on the other, the mouth of the bay is perilous. Near mid-channel, there is one reef that rises above the water, and so presents no danger in itself; a tower has been built on top of it, and a garrison is kept there. Since the other rocks lie under the water, they are very dangerous. The channels are known only to the Utopians, so hardly any strangers enter the bay without one of their pilots; and even they themselves could not enter safely if they did not direct their course by some landmarks on the coast. Should these landmarks be shifted about, the Utopians could easily lure to destruction an enemy fleet, however big it was.
On the outer side of the island, harbours are found not infrequently; but everywhere the coast is rugged by nature, and so well fortified that a few defenders could beat off the attack of a strong force. They say (and the appearance of the place confirms this) that their land was not always surrounded by the sea. But Utopus, who conquered the country and gave it his name (for it had previously been called Abraxa), and who brought its rude, uncouth inhabitants to such a high level of culture and humanity that they now surpass almost every other people, also changed its geography. After winning the victory at his first assault, he had a channel cut fifteen miles wide where the land joined the continent, and thus caused the sea to flow around the country.