Guyana the dryer savannah areas in the south-west; and the smallest interior lowlands (interior savannah) consisting mostly of mountains that gradually rise to the Brazilian border. Some of Guyana's highest mountains are Mount Ayanganna (), Monte Caburaí () and Mount Roraima ( – the highest mountain in Guyana) on the Brazil-Guyana-Venezuela tripoint border, part of the Pakaraima range. Mount Roraima and Guyana's table-top mountains (tepuis) are said to have been the inspiration for Sir Arthur Conan Doyle's 1912 novel "The Lost World". There are also many volcanic escarpments and waterfalls, including Kaieteur Falls which is believed to be the largest water
American Falls it was decided not to make alterations to the rockwall, citing the trend to allow nature to take its course. American Falls The American Falls is the second-largest of the three waterfalls that together are known as Niagara Falls on the Niagara River along the Canada–U.S. border. Unlike the much larger Horseshoe Falls, of which two-thirds is in Ontario, Canada and one-third in the U.S. state of New York, the American Falls is entirely within the United States. The falls receive approximately 11% of the flow from Niagara River, with most of the rest going over Horseshoe Falls, from which