Merli Menhir Nature · Isábena, La Ribagorza, Huesca Image of Isábena, not of the place itself. Menhir located in the municipality of Isábena (La Ribagorza, Huesca), near Roda de Isábena. It is an elongated rock whose visible height reaches 6 metres, with an estimated age of 5,000 years, one of the megalithic elements preserved in the small settlement of Merli. Photo: Dirkvde (CC BY-SA 3.0) What to see and do in Isábena