A substantial part of Davao City is mountainous characterized by extensive mountain ranges with uneven distribution of plateaus and lowlands. The mountain range that delimits the western boundary of the city extends as far down to South Cotabato. This mountain ranges nurses the highest peak in the Philippines, which is Mt. Apo located at the boundaries of North Cotabato, Davao del Sur and Davao City. Mt. Apo has an elevation of about 10.311 feet (3,144 meters) above sea level. It has been considered as semi-active volcano.
The large, contiguous lowland areas of Davao City are coastal plains and valleys extending inland as greatly-rising valleys. These areas are found in the eastern part of the city in Paquibato district, which is an extension of vast lowland at the head of Davao Gulf. The other substantial lowland located in the southeastern part of the city along the western coast of the Gulf, and are in the districts of Bunawan, Buhangin, Agdao, Poblacion, Talomo and Toril. These lowland areas are level to nearly land with slopes ranging from 0 to 3 percent. These are generally composed of recent alluvium consisting of clay, silt and some sand and gravel.
Topographically, along the southeast quarter is plain and slightly hilly along the entire coast and uplands north and westward to Calinan, with slopes generally below four to five degrees. The plains and valleys merged gradually into the uplands, and the uplands in turn into the mountains. Although the eastern part of the city is a broad lowland belt, its surface is interspersed by low hill and knobs.
The entire land area of Davao is drained towards the Gulf Davao River and its numerous tributaries are the main drainage system of the city. Davao River originates from Davao Province, flows towards the south meandering along the central part and finally flows eastward emptying into the gulf at the southern periphery of the City Proper. The secondary drainage outlet of the city is the Talomo River which is the drainage outlets of the eastern slopes of Mt. Apo. There are other small rivers and streams that drain the area, but Davao and Talomo Rivers are the important river basins.