Thousands of visitors crowded the Summer Palace's Nanhu Island in Beijing, on Sunday to admire the rare moment when all 17 arches of the longest bridge in the royal park were lit up by twilight. /Chinanews Photo

It is said that the Seventeen Arches Bridge was designed to be vertical with the sunset point of the Tropic of Capricorn under delicate calculations, which means the spectacular scene can only be seen in the days next to the Winter Solstice solar term every year.‍ /Chinanews Photo