The river that runs through Rome — Italy's third longest, starting in the Apennine mountains and flowing south and west to the sea. In English it almost always appears with "the" in front of it, like most river names: the Tiber, on the Tiber, across the Tiber. It matters far beyond its size because of Rome: the ancient city grew up on its banks, its bridges and its island are part of the old city centre, and the legend of Romulus and Remus has the twin babies set adrift on this river and washed ashore to be found by the wolf. So in writing about history, art, or literature, "the Tiber" is often a shorthand for Rome itself. It is a muddy yellow-brown river with high stone walls along it through the city, built after bad floods in the 1800s. Italians call it il Tevere, so a student who has been to Rome may know the Italian name and not recognise the English one.