Madrid: A haul of 600 kg of "hugely important" bronze Roman coins, was uncovered by workers in the Spanish town of Seville, the media reported on Thursday. The Andalusia Department of Culture said the coins, which date back to the fourth century, were discovered within 19 stone jars and looked as if they were deliberately hidden, Xinhua news agency reported. They were taken to a museum in Seville, where they are currently being examined by experts, who said they have never seen such an abundant haul of coins which are so similar to each other. The coins are thought to have been manufactured in the east of the Roman Empire and show few signs of use, which means they were probably never in circulation. It is thought they could have come from either tax revenue, or have been used to pay the army. After Romans' invasion in 218 BC, Spain became a key part of the Roman Empire, and indeed the hero of the film "Gladiator" was referred to as the "Spaniard". There are still many impressive pieces of Roman architecture standing in Spain, such as the Aqueduct in Segovia, north of Madrid, the Roman lighthouse, known as the "Tower of Hercules" in la Coruna, and the city of Merida, which has many impressive remains.