This Phoeni­cian city, where a tri­ad of deities was wor­shipped, was known as Heliopo­lis dur­ing the Hel­lenis­tic peri­od. It retained its reli­gious func­tion dur­ing Roman times, when the sanc­tu­ary of the Heliopoli­tan Jupiter attract­ed thou­sands of pil­grims. Baal­bek, with its colos­sal struc­tures, is one of the finest exam­ples of Impe­r­i­al Roman archi­tec­ture at its apogee.