There were formerly two entrances to the harbour - the Boca Grande (large mouth) between the low sandy island or peninsula on which the city stands and the island of Tierra Bomba, and the Boca Chica (small mouth) at the south end of the latter island.
African coast, lying between the Syrtis Major and Marmarica, the western limit being Arae Philaenorum, and the eastern a vague line drawn inland from the head of the gulf of Platea (Bomba).
In 1869 Ali Riza Pasha of Tripoli tried to induce settlers to go to Bomba and Tobruk; and in 1888 an abortive effort was made to introduce Kurds.
They have, however, the only good ports on the whole coast, Bomba and Tobruk..
It is the only safe port easily accessible to large vessels for over 1000 m., between Sfax in Tunisia and Alexandria, for, although there is safe and deep anchorage in the recess of the Gulf of Bomba, the entrance is rocky and difficult.