softened by the actions of tributaries of these two rivers such as the Pomahaka River. The rugged, scenic coastline of the Catlins features sandy beaches, blowholes, a petrified forest at Curio Bay, and the Cathedral Caves, which visitors can reach at low tide. Much of the coastline consists of high cliffs, up to in height, and the land rises sharply from the coast at most points. For this reason, many of the area's rivers cascade over waterfalls as they approach the ocean (notably the iconic Purakaunui Falls on the short Purakaunui River). The South Island's southernmost point, Slope Point, projects near the southwestern corner of the Catlins. To the west of this lies Waipapa Point, often considered the boundary of the Catlins region, beyond which lies the swampy land around the mouth of the Mataura River at the eastern end of Toetoes Bay. But various people place the western boundary of the Catlins region in different places, and some more stringent definitions exclude even Slope Point. A proposed boundary circulated in 2009 by the New Zealand Geographic Board ran roughly north from Slope Point, then inland around the Catlins Ranges and east to Nugget Point. Tourist organisations objected, asking that the boundary be moved further west to include Fortrose. Several parallel ranges of hills dominate the interior of the Catlins, separated by the valleys of the Ōwaka, Catlins and Tahakopa Rivers, which all drain southeastwards into the Pacific Ocean. The most notable of these ranges is the Maclennan Range. Between them, these hills are often simply referred to as the Catlins Ranges. Their northwestern slopes are drained by several tributaries of the Clutha and Mataura Rivers, most notably the Mokoreta River, which flows mainly westwards, reaching the Mataura close to the town of Wyndham. The highest point in the Catlins, Mount Pye () stands north-northeast of Waikawa and close to the source of the Mokoreta River, and marks part of the Otago-Southland border. Other prominent peaks above include Mount Rosebery, Catlins Cone, Mount Tautuku, and Ajax Hill. The Catlins has several small lakes, notably scenic Lake Wilkie close to the Tautuku Peninsula. Catlins Lake, near Owaka, actually consists of the tidal estuary of the Catlins River. Shipping has found the Catlins coast notoriously dangerous, and many shipwrecks have occurred on the headlands that jut into the Pacific Ocean here. Two lighthouses stand at opposite ends of the Catlins to help