VERY LITTLE OF STONEHENGE STILL EXISTS.
Salvaging useful materials is a well-established pattern of human behaviour. Stonehenge today consists of stones too large to cart away, and too big to be useful in the average new-build. 3000 – 4000 years of salvage has left fragments of what was there once.
Ironically the Temple that was Stonehenge, built to a symbolic plan incorporating classical elements (fire, earth air, water), was probably destroyed by fire.