 It is centered on the high water gap carved by the Marikina River in the southern Sierra Madre of northern Rizal province.The Montalban Gorge, also known as Wawa Gorge, has been a popular tourist destination since the Colonial Era and was widely regarded as one of the most remarkable natural features of Oriental scenery in the early 1900s.It is ringed by a series of marble boulders, limestone crags and up to tall white rock walls.