Several foothills can be observed here and there in this plain grassland. Some of the most prominent features are the Kalthota Escarpment and spectacular Diyavinna fall to the north and in the west the foremost park Ulgala Mountain and Bambaragala, Remanikotha rocky plains.
Elephants in number 450-600 exist in the park for now. Tall tree species like satin-wood (Choloxylon swietenia), Trincomalee wood alias Halmilla (Berrya ammonilla), ebony (Diospyros ebenum), Kolon (Adina cordifolia), Ceylon oak (Schleichera trijuga), chaste-tree (Vitex altissima) and KunumFalls (Diospyros ovalifolia) have dominated the park.
In the riverine forest at Walave River, Kumbuk (Terminalia arjuna) and the endemic Mandorang (Hopea cordifolia) are predominant. Savanna grasslands are dominated by Mana (Cymbogon confertiflorus) and Iluk (Imperata cylindrical) and the scrub is invaded by clustery vegetation of Damaniya (Grevia tiliaefolia). Besides, invading plants like Gandapana (Mappia ovate) and Kuretiya (Memecylon rostratum) have covered some areas of grassland.
As well as elephants among the large mammals, the spotted deer (Carvus axis), samber deer (Carvus unicolor), sand deer, Indian moose deer (Moschus miminna), wild boar (Sus scrofa) and water buffalo (Bubalus bubalis) are re-establishing themselves. Other mammals live in the park include jackal (Canis aureus), wandaroo or large monkey, monkey, golden musang (Paradoxurus zeylanicus), rabbit and polecat (Paradoxurus musanga).
About five species of mouse have been reported from the Thom-scrub now predominate. Leopard (Panthera pardus), Toddy cat (Paradoxurus hermaphrodities), small Indian civet cat (Viverricula indica) that belong to cat family and deer also live in this park. About 30 species of serpents and 3 species of mongoose (Herpestes griseus) have been discovered from this national park. Also it is home to numerous species of avifauna.
An internal road system including an entrance from Handagiriya area in Balangoda has been established specially with the anticipation of exploring hither to unknown areas of Udawalawa National Park. This project is done on financial provisions and guidance of Ministry of Tourism in Sabaragamuwa Province.
There is hardly any facility for tourists to cover the entire park due to the discomfort of travelling in land interrupted by water bearing grounds. The area that is newly open to the public is also a part of Udawalawa National Park. Fossils of Balangoda anthropoid considered to be the foremost joint of the chain of human linage in Sri Lanka have been discovered from the place named BFallsn Bandi Pelessa near Handagiriya in the park. Besides, a lot of antiquities can be sighted here though more than the visible are invisible under the cover of earth.
Historical areas of archaeological remains like Pilima Edda Aara (Pilimeddara), Ambethota, Ulgala, Pansal Kulugala, Vidiya Godaella and Vehera Godaella and much more undiscovered areas yet to be discovered can be witnessed in the park. Bio-diversity in this wilderness sanctuary is in a higher level. The entire eco-system which is home to numerous fauna species, foothills, rocky plains, wet lands, dry lands, thorn-scrubs and river-basins, can be happily mentioned as legendary compliment of Mother Nature.