In 1570, during the period of national isolation when Dejima was established upon the opening of the Port of Nagasaki, the Nakajima River's importance to trade made it the central artery of the city. In 1634, Japan's first Chinese-style stone bridge, the Spectacle Bridge, was constructed by Mokusunyoujo, the second-generation Chinese monk of Kofukuji Temple, Japan's oldest Chinese Temple. The bridge gets its name from its resemblance to a pair of spectacles when the arches of the bridges are reflected as ovals on the surface of the river. This bridge, along with Edo's Nihonbashi Bridge and Iwakuni's Kintaikyou Bridge, are considered the three most famous bridges in Japan. Although it is not well known, Spectacles Bridge was the inspiration for the Double Bridge of the Imperial Palace. By the end of the 17th century, following the construction of the Spectacles Bridge, numerous stone bridges were built for many of the roads that join the Nakashima River. It is said that these stone bridges were only constructed on roads that lead to temples when one stands at Teramachi.