One of the oldest and most important of the Celtic symbols are the standing stones, or menhirs, which are found throughout Western Europe and actually date back to pre-Celtic prehistoric eras.
The mysterious megalithic monuments such as Stonehenge are believed to have been solar and lunar observatories.
The position and site of the stones represented a kind of catalyst for cosmic energy, and as such they were of central importance in Celtic religious ceremonies and rites.
As with tree symbols, certain stones and groups of stones were believed to have special energy properties or to contain the spirit of a deity or hero.
Standing stones were generally a phallic symbol, representing masculine energy, fertility and power.
The female counterpart of the standing stones symbol is the sacred well, one of the most evocative of the Celtic symbols representing the feminine.
With the arrival of Christianity the standing stones were adopted by the monks, who carved Christian images on them and used them to mark the boundaries of their monasteries.
Many of the stones, in fact, appear to have been hewn and sculpted directly from standing stones.
The standing stones are one of the most powerful and mysterious of the Celtic symbols. Due to their extremely remote prehistoric origins, however, and the scarce documentary evidence regarding their functions, they remain to this day an enigma that will, perhaps, never be fully solved.
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