The town, which is the residence of a kaimakam, is built on two low limestone hills and its streets are paved with limestone blocks.
The streets of Valletta, paved with stone, run along and across the ridge, and end on each side towards the water in steep flights of steps.
The Erasistrateans paved the way for what was in some respects the most important school which Alexandria produced, that known as the empiric, which, though it recognized no master by name, may be considered to have been founded by Philinus of Cos (280 B.C.), a pupil of Herophilus; but Serapion, a great name in antiquity, and Glaucias of Tarentum, who traced the empirical doctrine back to the writings of Hippocrates, are also named among its founders.
The modern town lies at the foot of a rock, on which stands the old town with its steep rock-paved streets and fortified walls, commanded by the Fort Muzello.
There are many beautiful private buildings, broad and well-paved streets, numerous squares and public gardens.