Ingenieur Vol 80 ingenieur 2019 octoberfinal | Page 81

Below road-level linking passage between main administrative buildings. These kept the air cool while commuting as the temperatures in this region can reach up to 40°C in the summer. The arch shape of the tunnel helps to withstand the upper load. Right picture is another view of the underground passage with light entering from air wells used for ventilation as well as for natural lighting. Ruins of the residential units on the western side, where most residents fetched water from the river via the West Gate. The West Gate is 1.7m wide and 16.8m above the river bed. The systematically arranged stone structure shows that it was carefully fortified and was a strategic military focal point. There are also hidden observation holes on the north side of the West Gate. As I was leaving the engineering marvels in the Turpan district, the image of this once thriving ancient city having been abandoned for centuries conjured a nostalgic feeling. Perhaps the parting message at the museum summarised it best: Rebirth: Today when we stand on the terrace of Yar City (Jiaohe) and look into the distance, we see the ruined walls and loneliness. Sighing for the vicissitudes of more than 2,000 years and the relentless ages passing, we are also shocked by the grandeur of Yar City, and thus sincerely admire the wisdom of the ancient people. Here you will find harmonious co-existence of human beings and nature, civilisation’s achievements in home building, and a vigorous atmosphere around. The Yar Lake Valley under the terrace, also known as “Lovers’ Valley”, is a natural oxygen bar in all seasons. Here in this valley, there are tranquil apricot blossoms, elegant and graceful pear and peach blossoms, and fresh green grapes. 100-year old trees have witnessed lovers’ faithfulness and romances, and the murmuring streams chant the poem at “At dusk we water our horses on the Yar River”. History has endowed a new meaning on Yar City, and that is Yar City, as one of the world heritage sites, should inherit the wisdom and civilisation of human beings and carry forward national harmony and prosperity. REFERENCE Office for Preservation and Conservation of the Ruins of Jiaohe under the Cultural Bureau of Xinjiang Uygur Autonomous Region & Turpan Prefecture Bureau of Cultural Relics. Jiaohe Museum Wikipedia 79