Thaba Bosiu is a constituency and sandstone plateau with an area of approximately 2 km2 (0.77 sq mi) and a height of 1,804 meters above sea level. It is located between the Orange and Caledon Rivers in the Maseru District of Lesotho, 24 km east of the country's capital Maseru. It was once the capital of Lesotho, having been King Moshoeshoe's stronghold.

Maseru is a district of Lesotho. Maseru is also the name of the district's capital, and is the only city in the district and also the capital of the country. It is the largest urban area in the country, and therefore the only city. The city of Maseru is located on Lesotho's western border with the Free State Province of South Africa, the frontier being the Caledon River. Maseru borders on Berea District in north, Thaba-Tseka District in the east, Mohale's Hoek District in south, and Mafeteng District in southwest.