Four priceless bronze animal heads, seized by foreign troops over 140 years ago, have been on display since Sunday in Guangzhou, capital of southern Guangdong province, following their return to China. It was the first time the four invaluable bronze artworks were exhibited together in Guangzhou's Huangpu district after their long absence overseas, archaeologists said. The four bronze heads of ox, tiger, monkey and pig were all very rare, state-level cultural relics, which were placed at the imperial Yuanmingyuan Garden during Qing Dynasty (1644-1911). In compliance with the designs of European clergy, eminent Qingcourt mater craftsmen forged a total 12 bronze heads of symbolic animals, representing the people's birth years in the 12-year cycle. The 12 heads constituted part of a water clock fountain, letting out water in turn everyday, archaeologists said. They were all seized and pillaged by British and French Allied Forces During the second Opium War (1856 to 1860). However, nearly one and a half centuries later, the four priceless bronze heads were purchased by patriotic personages and brought back to China between 2000 and 2003.