Arts, sciences, international trade, a highly developed economy and a surprisingly advanced technology prospered in Constantinople. With nearly one million inhabitants, Constantinople was one of the biggest cities of her time. It is thus not surprising that Constantinople aroused desires among her enemies time and again. Virtually uninterrupted defensive action against the Arabs characterized the 8th century. In 717, only a few months after Leo III had been crowned emperor in the Hagia Sophia (until 741), the Arabs were even standing at the city gates. Leo managed to overcome the siege finally after a year. This solidus was among Leo's earliest mintages. The obverse depicts the emperor, while a cross potent figures on the reverse.