Loulan, an ancient city in the Lop Nur, was first "discovered" by Swedish explorer Sven Hedin in 1900. The finding of Loulan brought about new and unexpected fame for the ancient history of the Central Asia and thus began the exploration of the Taklamakan Desert. The City of Loulan is known both in China and throughout the world as the Middle Kingdom's ' _ ' in the desert and one of the cradles of the civilization. It wasn't hard to imagine how excited Sven Hedin must have been when he was awarded the Victoria Medal by the Royal Geography Association. From that point forward, the mysterious covering of Loulan was gradually lowered and was no more a silent unknown hero but became an immediate worldwide sensation  . Adventurers from America, Britain, Japan and Sweden, including Huntington, Stein, Otani Kozui and Bergman set foot here for several times. In the 1930s, Chinese archaeologist Huang Wenbi came here for the first time and made a survey of this area, which was found even then in terrible conditions due to uncontrolled digging with many wonderful cultural historic relics taken away to distant foreign lands. In 1979, a group of tombs called Sun Tombs, known for their unique and attractive burial forms, were unearthed in the Gumugou Graveyard, the public graveyard of the Lop Nur citizens in the Bronze Age. In early 1980s, in the Tiebanhe River Delta area of the lower reaches of the Peafowl River in Lop Nur, a female mummy dating back some 3,800 years was unearthed and was considered by the Japanese as the "Loulan Beauty". This set off a wave of current exploration of the Silk Road. The archaeological unearthing being currently conducted in the Xiaohe (Small River) Graveyard is now the focus of the world's most important academic event. The Xiaohe Graveyard, 175km west of the City of Loulan, is located in the lower reaches of the Peafowl River in the Lop Nur. When the Graveyard was found, it is said that there were some 1,000 coffins. It is large in scale with sand dunes  as high as eight metres, on which about 140 wooden stakes  in various shapes were closely arranged. These burial customs are, to say the least, unusual... with the unearthed relics dated back to China's most ancient days. Which of the following is the closest in meaning to the word '  _  '?
A city as world famous as the Middle Kingdom's "Pompeii". A buried city in the desert with great historical value. A buried city to be unearthed like the Italian city "Pompeii". A city visited by many archaeologists all over the world like "Pompeii".