The Kletsel Dehe Wintun Nation of the Cortina Rancheria is a federally recognized tribe of Indigenous people of California.

[2] They are Wintun people, who historically spoke Wintuan languages.

They're headquartered in Williams, California,[2] and they have approximately 270 enrolled citizens.

[2][4] The Cortina Rancheria is an Indian reservation in Colusa County, California, at an elevation of 1,312 feet (400 m).

[5] The tribe partnered with California State University, Chico, to study water quality and purification systems.