In 595 BC, the affairs of the Oracle were felt too important to be left to the Delphians alone, and the sanctity of the site came to be protected by the Amphictyonic League, a league of 12 cities in existence since 1100 BC. In that year, nearby Kirra levied a toll on pilgrims, which ushered in the First Sacred War. After 5 years of struggle, the Oracle decreed that the site of Kirra be left fallow, sacred to Apollo. This ushered in a period of great prosperity.