Research shows that humans have already been living in the region of todays Hong Kong 30,000 years ago, and presumably made their living by trading salt. Because of the valuable position it held in trade, the latter Chinese fishing city was of more and more interest among the countries of the Western world, and after the first Opium War in 1842, it was subjugated under British authority. Starting in 1898, the second Opium War secured a 99-year lease for the British crown. Under British rule, the city went through some major developments; they established the first electric companies and bank; bus and train networks replaced rickshaws, airports were built, and a Western education system replaced the previously dominant Eastern philosophy system. In 1997, the city was returned to China, but for fifty more years it is to remain a self-governing province.