1921 by the amateur archaeologist Alfred Watkins, in his books Early British Trackways and The Old Straight Track. Watkins theorized that these alignments were created for ease of overland trekking on ancient trackways during neolithic times and had persisted in the landscape over millennia. Greece Improvements in metallurgy meant that by 2000 BC stone-cutting tools were generally available in the Middle East and Greece allowing local streets to be paved. Notably, in about 2000 BC, the Minoans built a paved road from Knossos in north Crete through the mountains to Gortyn and Lebena, a port on the south coast of the island, which had side drains, a thick pavement of sandstone blocks bound with clay-gypsum mortar, covered by a layer of basaltic flagstones and had separate shoulders. This road could be considered superior to any Roman road. The Via Pythia (or Pythian road) was the route to Delphi. It was revered throughout the Ancient Greek world as the site of the Omphalos stone (the centre of the earth and universe). The Sacred Way (, ), in ancient Greece, was the road from Athens to Eleusis. It was so called because it was the route taken by a procession celebrating the Eleusinian Mysteries. The procession to Eleusis began at the Sacred Gate in the Kerameikos (the Athenian cemetery) on the 19th Boedromion. In the present day, the road from central Athens to Aegaleo and Chaidari (the old route to Eleusis) is called after the ancient road. Ireland The Corlea Trackway is an ancient road built on a bog consisting of packed hazel, birch and alder planks placed lengthways across the track, and occasional cross timbers for support. Other bog trackways or "toghers" have also been discovered dating to around 4000 BC. The Corlea trackway dates from approx 148 BC and was excavated in 1994. It is the largest trackway of its kind to be uncovered in Europe. Ireland's prehistoric roads were minimally developed, but oak-plank pathways covered many bog areas, and five great 'ways' () converged at the Hill of Tara. An ancient avenue or trackway in Ireland is located at Rathcroghan Mound and the surrounding earthworks within a 370m circular enclosure. The Esker Riada, a series of glacial eskers formed at the end of the last Ice Age, formed an elevated pathway from east to west, connecting Galway to Dublin. Russia The Siberian Route (, ), also known as the