Kirsti Ellef Skagen (neé Dotter; 8 May 1788 — 24 November 1897) was a Norwegian centenarian and the first person verified to reach the age of 109, and at the time of her death was the oldest person ever, though her record has since been surpassed numerous times. She was born as Kisti Ellef Dotter in Luster, Norway. Her parents were Ellef Johannsen and Marte Arnesdatter.
On 1825, she married Henrik Olsen. The couple had one daughter, Sophie born in 1832. Henrik died in 1878.
Skagen died on 24 November 1897, at the age of 109 years, 200 days.