The use of sacred geometry (mathematically determining the relationship of an object with its surroundings to maintain a harmonious balance) has been noted when studying the placement of stones. The landscape seems to envelope many of the sites with at least one side open for a long-range view of the horizon. This type of harmony with the earth seems to have been used in later times for the placement of the palace of Knosses in Crete, and the temples at Delphi in Greece. On an even wider scale, many of the Neolithic monuments are in alignment with each other along Ley Lines, earth energy lines. If you were to draw lines on a map of England to connect the major sites, you would create a triangle.

Stonehenge and Ireland's Newgrange are the most well-known sites, but the Brittany coast of France has the greatest concentration of Neolithic monuments. The Gauls called Brittany the "land on the sea". A map of the Neolithic sites there reveals that they are scattered around inlets, rivers, and on a peninsula across the bay from the Grand Menhir. The word menhir comes from Welsh: maen (stone) and hir (long). Now broken and lying on the ground, the Grand Menhir would have been 60 feet tall. Within a five-mile area there are 3,000 stones. Approximately one-third of them stand in rows (running east to west) several kilometers long that lead toward large semi-circles of stones. The height of the alignment stones gradually increase from two to twelve feet as they near the semi-circles. Major sight lines for the midwinter and midsummer moonrises and moonsets intersect at the Grand Menhir.

Material from burials in the chambered mounds at Carnac have been dated to 4700 BCE. While the area is densely populated with monuments, archaeological work around the sites reveal that not many people actually lived in the immediate vicinity which suggests that it functioned as an observatory and place of ritual. Here as well as other sites in Europe, level areas of paving stones would suggest an ideal route for processions and dancing. To the people who built them, science and religion were probably not separate compartments for exploration and belief. To observe and honor the natural world and feel truly connected with it must have made for powerful rituals and celebrations at Carnac. Even into historical times, people of Brittany marked the quarter days of the year with festivals and dancing among the standing stones.