The Temple of Jupiter is a colossal Roman temple, the largest of the Roman world, situated at the Baalbek complex in Heliopolis Syriaca (modern Lebanon). The temple served as an oracle and was dedicated to Jupiter Heliopolitanus. It was the biggest temple dedicated to Jupiter in all the Roman Empire. The columns were 19.9 meters high with a diameter of nearly 2.5 meters: the biggest in the classical world. It took three centuries to create this colossal temple complex.