The Siq is a narrow natural gorge leading to Petra's Treasury that resulted naturally from a splitting of the mountain, and it is just over 1 km long.  Before its entrance, a tunnel was constructed by the Nabataeans to redirect the flash floods of Wadi Musa from the Siq to Wadi Al Mudhlim and Wadi al Mataha. This 88-meter-long tunnel was carved into the rock for this purpose. A triumphal arch once spanned the entrance to the Siq, but this collapsed in 1895. Two water channels run along both rock sides. As well as presenting a dramatic entryway into Petra, the Siq also holds many relics from Petra’s past. These include a paved road, Sabinos Alexendros Station, and some other Nabataean baetyls (sacred stones). The paved road was originally constructed by the Nabataeans at a lower level, and the Romans repaved this central thoroughfare after the annexation of Nabataea in AD106.  Walking through the Siq is like stepping back in time, surrounded by history and the impressive natural beauty of the rock formations. It is truly a unique and unforgettable experience for visitors exploring the ancient city of Petra.   As visitors walk through this narrow passage, they can imagine what life was like in Petra thousands of years ago.