Maiden's Bower is a Bronze Age round cairn built in Flass Vale Nature Reserve, in Durham, England.

Maiden's Bower dates back to around 3,000 years ago, when people settled in the area and started clearing Flass Vale for pasture.

Before the Battle of Neville's Cross the Durham monks, led by Prior John Fossor, raised the holy corporax cloth from St. Cuthbert's tomb as a banner on the cairn during a vigil.

[5][6] Maiden's Bower was protected as a scheduled monument in 1926, and in 1990 Flass Vale was designated as a local wildlife site.

In 2023 geophysical and earthwork surveys were conducted at Maiden's Bower led by Durham University.