Esmé Kirby (born Esmé Cummings, 31 August 1910, Croydon, died 18 October 1999, Snowdonia), was a conservationist who formed the Snowdonia National Park Society in 1958 to ensure the mountains would be protected from future development.
After she finished her education at Arne Hall School in Llandudno, she became an actress and then a horse riding instructor.
In 1939 she married Thomas Firbank, whose bestseller I Bought a Mountain describes their life at the hill farm Dyffryn Mymbyr during the 1930s.
In 1938, they walked the Welsh 3000s, 14 peaks over 3000 feet, in 9 hours, 29 minutes, setting the women's record at that time.
They bought Tŷ Hyll (The Ugly House) to become the headquarters for the society and remodelled the gardens.