Rinca Island lies at the most Eastern part of the Komodo National Park area, and is separated from the land surface of Flores by a narrow strait called Strait Molo. The island is rounded to the South with rugged topography, and on the North side it is split in two by a bay called Loh Kima. The island has a surface area of around 211 km2, has a total coastline of 172 km, and stretches over a distance of 28 km from Southwest to Northeast. Mt. Doro Ora in the South reaches 667 m above sea level and is the highest mountain on Rinca. The highest mountain in the Northeast part is Mt. Pankarmea (542 m), which forms a rugged mountain range together Mt. Doro Radja (351 m) and several other peaks. In the central and Northwest part the island has a more sloping topography, with small stretches of white sandy beaches. The South coast contains steep cliffs, and sloping narrow beaches.
The island is influenced by the monsoon winds, so that from November through March the Northwesterly winds blow, carrying a lot of water. During the months of April to October dry winds blow from the Southeast, and there are droughts.
In addition to the well-known Komodo dragon, a population of feral horses is found on this island. The wild horse population is found only in the region between Rinca village and Kerora village, and overlaps with the distribution of the wild buffalo. There are also feral dogs present, which compete with the Komodo dragon for food resources, such as deer, wild boar, rodents, birds, and carrion. In addition, they prey on young Komodo dragons. The feral dog population needs to be eliminated. The long-tailed macaque (Macaca fascicularis) is found on Rinca, but not Komodo or Padar islands. This primate species is able to swim, and crossed the narrow straits from Flores. The wider straits between Rinca, Padar and Komodo probably prevented their dispersal further Northwest. Deer (Cervus timorensis) are often found in the region of Mt. Tumbuh and Doro Ora up to Loh Dasami. In addition, the wild boar (Sus scrofa) population is quite numerous and distributed from the coast up to the savanna woodland and deciduous (monsoon) forest. Wild pigs compete with Komodo dragons for carrion.