Today, as a result of revenue from oil, Abu Dhabi is one of the world's richest cities, with wide, tree-lined okulevards, lush green parks, gushing fountains and imposing skyscrapers. Somewhat of a dichotomy, Abu Dhabi is a combination of ultra-modern sophistication and Arab mystique, with friendly and hospitable people offering a warm welcome to visitors. Abu Dhabi's history originated in the 18th century, when, according to legend, a group of tribesmen pursuing a gazelle came upon a freshwater well which they named Abu Dhabi, or "Father of the Gazelle". In the 19th century, the first fort was built over this well by a sheikh of the Al-Nahyan dynasty. The fort's name is Al Husn Palace, also known as Old or White Fort, and it is one of the few buildings in Abu Dhabi that is more than 25 years old. Its whitewashed walls are eye-catching amid the backdrop of today's skyscrapers. Presently, it is home to the Cultural Foundation and serves as a documents centre. Abu Dhabi had little significance until the discovery of vast oil reserves in the late 1950s and early 1960s. In the years following, the city's economy and infrastructure developed rapidly and changed Abu Dhabi beyond recognition.