Residents of Dandong, a city bordering North Korea in Northeast China's Liaoning Province, welcomed a new attraction on Saturday night: a colorful display of lights on the city's landmark bridge over the Yalu River, which was installed over the summer with some suggesting the upgrade is in honor of North Korea's forthcoming National Day.Dandong's Zhenxin district urban construction bureau started in July to replace the existing lighting system over the "Broken Bridge" which is so named because it was bombed during the war and the missing section connecting to North Korea was never repaired. A new bridge, the China-North Korea Friendship Bridge, was built alongside the Broken Bridge.The new, flashing light display was turned on Saturday, the local bureau said according to a report by the local Dandong Daily on Saturday.According to the bureau head, surnamed Xiao, the city is also working on a new lighting system for the China-North Korea Friendship Bridge that will be completed by the end of September.The goal of the lighting projects on the bridges is to improve the image of China's gateway city to North Korea and to show the country's achievements during four decades of reform and opening up, the article said.The colors in the light display have been purposefully chosen to send a message, Dandong authorities explained in the article. Red represents the city's status as a "red tourism" hot spot, blue underscores the city's steel-like spirit, and yellow is the color of the city's adopted tree, the ginkgo.The old lighting system over the bridges was just one color but the new system's red, blue and yellow will be much brighter and prettier, a Dandong resident surnamed Tao, told the Global Times on Sunday.According to Tao, Chinese flags have been attached to every beam to the half way point of the steel bridge and the lighting system was on Sunday afternoon.Lü Chao, a research fellow at the Liaoning Academy of Social Sciences, told the Global Times on Sunday that such a spectacular light show could be China's tribute to North Korea on its upcoming National Day on September 9.Because the bridges witness the enduring friendship between China and North Korea, colors on the light show reflect the colors of the two countries' national flags, Lü noted.According to data from Dandong's local statistics department, the number of tourists traveling to the city increased 12.9 percent year-on-year in 2017.Total tourism revenue growing at the same pace. although exact figures are not available, said the department.