celtic vetton sacred space nemeton altar of sacrifices sculpted in granite. near san lorenzo del escorial, madrid, spain

abantos acer attraction beautiful celtic celts clouds encina escorial europe forest granite heritage hill historic iberian ilex king landmark landscape legend machota madrid maple monarch monspessulanum montpellier moss mount mountain national nature outdoor park patrimonio pyrenaica quercus roble scattered seat sierra sightseeing sky spain stone tourism touristic travel tribe