Mining town of Novo Brdo is considered one of the major examples of this. Described by Constantine of Kostenets as a "truly gold town" in the 15th century, gold and silver mine was surrounded by the town which had a population of 40,000 in 1434 (more than London, England). Due to its size and affluence, it was nicknamed "majka svih gradova" ("mother of all towns"). Novo Brdo had a sewage system and street lights. Miners worked 6 hours a day, had uniforms, their own mining anthem, music and flag, while two times a year they had right to go on a vacation, in which case they were awarded 3 gold coins "for the road". In that same year, there were 125 different consuls from foreign states and cities residing in Novo Brdo. The first legal document which regulated economic relations in mediaeval Serbia ("Law on Mining") was adopted in Novo Brdo, by the orders of despot Stefan Lazarević. Though close to the location of the Battle at Kosovo in 1389, it succumbed to the Ottomans only 66 years later, in 1455. Despite greatness and richness, the mine survived only until the late 16th century, when the mining completely stopped.