The
massive stone that make up the extraordinary monument of Stonehenge near
Amesbury in Wiltshire were collected and arranged over the course of some
1,400 years between 2750 and 1300 BC. There were altogether around 150
stones, some brought from quarries in Wales, some 22 ft (6.7m) high, and
some weighing about 45 tonnes. The exact purpose of the careful arrangement
of the stones in the various interconnecting circles remains unclear. However,
a number of astronomical parallaxes relating to both solar and lunar calendars
have been established on a historical basics. The stonehenge's axis was
aligned with the rising sun on the longest day of the year in the northern
hemisphere (21st June). It is possible that such astronomical events formed
the focus of religious ceremony.