Sitting just outside Rabat's Almohad-era walls and standing sentry over the river that has served the city since ancient times, the Chellah is both a Roman ruin and Islamic burial place. As the Roman city of Sala Colonia, it was a bustling trading post of the empire's southernmost colony from A.D. 40 onward, and was one of the last to eventually sever links with the empire. Signposted as SITE ANTIQUE, the mainly scattered ruins include a main road, the Decumanus Maximus, that passes through a triumphal arch and past the Jupiter Temple (on the left), coming to an end at the forum. The city was finally abandoned in 1154 for the new settlement of Salé, across the river. Used as a royal burial ground by the Almohads, the site was extended into a holy necropolis, or chellah, by the Merenids, in the 14th century. Most visible today is a tall stone-and-zellij minaret and a small theological school, or medersa. Near the minaret is the tomb of one of the greatest Merenid rulers, Abou el Hassan, who was known as the Black Sultan. El Hassan's rule saw the entire Maghreb (Tunisia, Algeria, Morocco) under Merenid control. There's no one great sight within the ruins, but it remains a visible reminder of the historical significance that the city of Rabat has held. It's a pleasant and tranquil place to wander around; the ruins are overgrown with aged fruit trees and are habituated by a colony of storks, which is considered a sign of good fortune.