The UAE's currency was introduced on May 20, 1973, a little more than two years after the country was formed. Prior to the dirham, the rupee, dinar and even the Maria Theresa silver thaler were used. In this weekly series, <em>The National</em> breaks down the historical and cultural significance of the designs for each of the dirham denominations. The magnificent profile of an Arabian oryx and its sweeping curved horns is the unmistakable face of the Dh50 note. The motif is continued with the silver foil watermark, which shows an oryx in profile. The English language side shows Al Jahili fort in Al Ain, built in the 1890s on the orders of Sheikh Zayed bin Khalifa, often called Zayed the Great, as a home for Al Nahyan ruling family. One of the original banknotes issued in 1973, the Dh50 first depicted the Ruler’s Palace in Ajman and was printed in red. The current design, using purple inks, dates from 1982. At the time of issue the Arabian oryx was on its way back from near extinction, with a breeding programme at Al Ain Zoo leading to their reintroduction in the wild. It is estimated that about 5,000 now live in a wildlife reserve in Al Dhafra. Al Jahili Fort has also been given a new lease of life. It served as the headquarters of the Trucial Oman Scouts from the 1950s but has now been fully restored as a cultural and education centre, as well as one of the city's most historic attractions.