Holm oak of Covas Nature · Rubiá, Valdeorras, Ourense A holm oak (Quercus ilex subsp. ballota) legally recognised as a singular tree by the Xunta de Galicia, standing beside the access road to the place of Covas, in the parish of the same name, within the Serra da Enciña da Lastra. It stands 18 metres tall with a trunk perimeter of 650 centimetres at the base, from which three thick branches emerge; it is estimated to be about 500 years old. Photo: Estevoaei (CC BY-SA 4.0) What to see and do in Rubiá