Somapura Mahavihara or Paharpur Buddhist Vihara in Paharpur, Badalgachhi, Naogaon, Bangladesh is among the best known Buddhist viharas or monasteries in the Indian Subcontinent and is one of the most important archaeological sites in the country. It was designated as a UNESCO World Heritage Site in 1985. It is one of the most famous examples of architecture in pre-Islamic Bangladesh. It dates from a period to the nearby Halud Vihara and to the Sitakot Vihara in Nawabganj Upazila of Dinajpur District.

Bangladesh, officially the People's Republic of Bangladesh, is a country in South Asia. It is the eighth-most populous country in the world and is among the most densely populated countries with a population of nearly 170 million in an area of 148,460 square kilometres (57,320 sq mi). Bangladesh shares land borders with India to the north, west, and east, and Myanmar to the southeast. To the south, it has a coastline along the Bay of Bengal. It is narrowly separated from Bhutan and Nepal by the Siliguri Corridor, and from China by the mountainous Indian state of Sikkim in the north. Dhaka, the capital and largest city, is the nation's political, financial, and cultural centre. Chittagong, the second-largest city, is the busiest port on the Bay of Bengal. The official language of Bangladesh is Bengali while Bangladeshi English is also used in the government and official documents alongside Bengali.