deity involved was usually Nemetona – a Celtic goddess. Druids oversaw such rituals. Existence of such groves have been found in Germany, Switzerland, Czech Republic and Hungary in Central Europe, in many sites of ancient Gaul in France, as well as England and Northern Ireland. Sacred groves had been plentiful up until the 1st century BC, when the Romans attacked and conquered Gaul. One of the best known nemeton sites is that in the Nevet forest near Locronan in Brittany, France. Gournay-sur-Aronde (Gournay-on-Aronde), a village in the Oise department of France, also houses the remains of a nemeton. Nemetons were often fenced off by enclosures, as indicated by the German term Viereckschanze – meaning a quadrangular space surrounded by a ditch enclosed by wooden palisades. Many of these groves, like the sacred grove at Didyma, Turkey are thought to be nemetons, sacred groves protected by druids based on Celtic mythology. In fact, according to Strabo, the central shrine at Galatia was called Drunemeton. Some of these were also sacred groves in Greek times (as in the case of Didyma), but were based on a different or slightly changed mythology. Germanic paganism Trees hold a particular role in Germanic paganism and Germanic mythology, both as individuals (sacred trees) and in groups (sacred groves). The central role of trees in Germanic religion is noted in the earliest written reports about the Germanic peoples, with the Roman historian Tacitus stating that Germanic cult practices took place exclusively in groves rather than temples. Scholars consider that reverence for and rites performed at individual trees are derived from the mythological role of the world tree, Yggdrasil; onomastic and some historical evidence also connects individual deities to both groves and individual trees. After Christianization, trees continue to play a significant role in the folk beliefs of the Germanic peoples. Today Europe Estonia Based on historical data, it is estimated that there are around 2500 sacred natural sites in Estonia, the largest of them covering up to 100 hectares. Although rather exceptional among most of the technologically developed countries, in Estonia both the sacred natural sites and indigenous customs connected to them are still in use. Therefore, the heritage that is connected to sacred natural sites has great importance to the national identity and environment of Estonians. In a collaboration between followers of Estonian native religion (Maausk) and governmental ministries, a national plan was prepared in 2008: