By the beginning of the eighteenth century, the population of Tokyo had grown about 1 million, making it the largest city in Japan and one of the most populous in the world. An especially lively section of the city was along the Sumida River, where pleasure boats and parties were common and whose banks were lined with fashionable tea-houses. Tea was central to the Japanese not only in their homes, but in the public life as well. In the bustling urban centres of 18th-century Japan, tea-houses served a role similar to the one played by coffee-houses in Europe which were centres of discussion and entertainment.