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These ' Solar Trenches ' on the Piha Rd Ridge over looking the Pacific Ocean , were built by an Ancient Race of People to tell them what time of year it was for Ceremonial, agricultural , fishing & navigational purposes. At the ' Equinox ' & ' Winter Solstice ' the setting Suns rays ,on the Seas level Horizon, would shine along the appropriate trench and 'light up' a marker inside the shaded ' Cave '. This very accurate form of time measurement has been used by numerous Ancient civilizations including the Egyptians, and shows a developed level of Astronomical intelligence. This site is one of a number of Astronomical sites in the area, others include leveled hilltops with 'shadow hollows', carved stone 'Sun Dials', & pyramid type hills with placed alignment stones on the top.
The following photograph is of an Pyramid Complex used for Astronomical observation of the Sun, Moon, Planets & Stars.Located on the shores of Northlands East Coast the community who built this site have long since faded into the unknown, however their structures have continued to be used by each preceding culture up to the time of the Maori. Again this site has a level Ocean Horizon in the East which allows for accurate calculation of Celestial events for planting, harvest, fishing & Ceremony. Much of this site remains un-surveyed, yet undoubtedly holds many secrets including Caves, hidden alignments & treasure !