A detailed laser-scan survey of the entire monument discovered prehistoric art works invisible to the naked eye, including 71 Bronze Age axe-heads and one image portraying a Bronze Age dagger.
The survey recorded billions of points micro-topographically on the surfaces of the monument's 83 surviving stones. In total, some 850 gigabytes of information was collected, The Independent reported.
Detailed analysis of that data - carried out on behalf of English Heritage - found that images had been engraved on the stones, normally by removing the top 1-3 millimetres of weathered (darker coloured) rock, to produce different sized shapes.
The 72 new 'rock art' discoveries almost treble the number of carvings known at Stonehenge and although now largely invisible to the naked eye, back in the Early Bronze Age the images, composed of then-unweathered (and therefore lighter coloured) stone would have been clearly visible.
It's known that, when the main phase of the monument was initially built in the middle of the third millennium BC, it was designed primarily as a solar temple, aligned on the mid-winter and mid-summer solstices.
However, as Stonehenge evolved over subsequent centuries, the extent to which other religious functions were added is not yet known.
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In the period 1800-1500 BC, vast numbers of individual monumental tombs were constructed in the landscape around Stonehenge and additional features (various circles of ritual pits) were laid out around the monument.
The carved axe-heads and daggers also belong to this enigmatic period - and may signify some sort of expansion or change in the great stone circle's religious function.
The laser-scan survey was carried out for English Heritage by a Derby-based survey company - the Greenhatch Group - last year.
A subsidiary of York Archaeological Trust