It is protected area in Uttar Pradesh that stretches mainly across the Lakhimpur Kheri and Bahraich districts.
It comprises Dudhwa National Park, Kishanpur Wildlife Sanctuary and Katarniaghat Wildlife Sanctuary.
It covers area of 1,284.3 km2 and includes three large forest fragments.
It shares north-eastern boundary with Nepal, which is defined to large extent by Mohana River.
The area is vast Terai alluvial floodplain traversed by numerous rivers and streams flowing in south-easterly direction.
It ranges in altitude from 110 to 185 m.
Apart from tigers (estimated 106–118), it is also home to swamp deer, sambar deer, barking deer, spotted deer, hog deer, Indian rhinoceros, sloth bear, ratel, jackal, civets, jungle cat, fishing cat, etc.
It is home to one of finest forests in India, some of these trees are more than 150 years old and over 70 ft tall.