Standing isolated surrounded by the vast , golden north Saudi Arabian desert is a bizarre single rock castle , which has been lying undisturbed for centuries . Qasr al-Farid or 'The Lonely Castle ' has a sad tale , standing incomplete and abandoned , looking out of place in the vast , barren landscape . Believed to be constructed in the first century A.D. and situated on one of the most important ancient trade routes , linking the north and south of the Arabian peninsula , the mysterious monument was never finished . Scroll down for video . Now a UNESCO World Heritage Site , the ancient remains of Qasr al-Farid - a rock-cut tomb and part of an ancient Nabatean settlement - stands amidst imposing cliffs and striking rocky outcrop . The Nabatean Tomb in Madain Saleh is located in the northwestern region of the Arabian peninsula , in the middle of a vast desert landscape . Size matters ! The striking structure is the largest of the 131 tombs in the area , hinting it was intended for someone of great power . Despite its misleading name , the fascinating four-storey monument was actually used as a tomb . It 's intricate carving borrows decorative elements from Egyptian , Hellenistic , and Assyrian architecture . The tomb is the largest of 131 monumental tombs , which were carved straight into rock in the city of Mada'in Saleh during the pinnacle of Nabatean era . And it is famous for standing completely alone . Size would have been indicative of the person 's social status and wealth , hinting it was intended for someone of power . It is remarkable how The Lonely Castle has remained so preserved against the elements for over 1,900 years and this can be attributed to the dry climate . Situated on a pre-Islamic archaeological site located in Al-Ula , is located on one of the major trading sites , which linked the south of the Arabian peninsula to the north . Unesco declared the magnificent historic collection Saudi Arabia 's first World Heritage site in 2008 . Nabataeans constructed their massive stone buildings mainly from single pieces of sandstone , and carved from the top down . If the smooth stone reminds you of the iconic carved site of Petra in Jordan , it should come as no surprise to learn they are linked . Petra was the capital of the Nabataean kingdom and features a 250-foot-high sandstone slot canyon known as the Siq . Until 1812 , the site was unknown to the western world until it was introduced by explorer Johann Ludwig Burckhardt . While Petra was the capital of the Nabatean kingdom , Mada'in Saleh was its second city , explaining why the unusual carved rock architecture is so similar . Petra in Jordan was the capital of the Nabatean Kingdom . It displays similar architecture design to Qasr al-Farid , being carved out of a single stone body . It is sometimes known as the Rose City due to the color of the stone . Impressive collection ! Another Saudi Arabian Nabatean tomb , Qasr al-Bint , has been perfectly preserved in the dry climate . UNESCO declared the historic series of tombs Saudi Arabia 's first World Heritage site in 2008 .
Johann Ludwig Burckhardt or 'The Lonely Castle ' has been standing strong since the first century AD . The single-rock tomb is incomplete and abandoned , but fascinatingly reveals structures were carved from top down . The striking castle is one of 131 tombs from the Nabatean Kingdom , located in the Al-Ula sector .