Siddharthanagar (Nepali: सिद्धार्थनगर), formerly and colloquially still called Bhairahawa (Nepali: भैरहवा), is a municipality and the administrative headquarter of Rupandehi District in Lumbini Province of Nepal, 265 km (165 mi) west of Nepal's capital Kathmandu.

It is the closest city to Lumbini, the birthplace of Gautama Buddha, which is located 25 km (16 mi) to the west.

The city's current name Siddharthanagar derives from Buddha's given name Siddhartha, as the birthplace of Buddha is located only 25 km (16 mi) to the west.

The name was changed to Siddhartanagar in 1977 AD[3] by poet Komal Dutta Tiwari.

[9][10] Bhojpuri is spoken by 42.2%, Nepali by 40.7%, Awadhi by 5.9%, Magar by 1.9% and Hindi by 1.9% of the Siddharthnagar municipality population as their first language.