Harold St George Gray
... that archaeologist Harold St George Gray discovered that the 11 m (36 ft) deep ditch surrounding Avebury was dug from solid chalk using red deer antlers as picks?
... that archaeologist <b id="mwCJE"><a href="./Harold_St_George_Gray" id="mwCJI" rel="mw:WikiLink" title="Harold St George Gray">Harold St George Gray</a></b> discovered that the <span about="#mwt46" data-mw='{"parts":[{"template":{"target":{"wt":"convert","href":"./Template:Convert"},"params":{"1":{"wt":"11"},"2":{"wt":"m"},"3":{"wt":"ft"},"abbr":{"wt":"on"}},"i":0}}]}' id="mwCJM" typeof="mw:Transclusion">11</span><span about="#mwt46" typeof="mw:Entity"> </span><span about="#mwt46">m (36</span><span about="#mwt46" typeof="mw:Entity"> </span><span about="#mwt46">ft)</span> deep ditch surrounding <a href="./Avebury" id="mwCJQ" rel="mw:WikiLink" title="Avebury">Avebury</a> was dug from solid chalk using <a href="./Red_deer" id="mwCJU" rel="mw:WikiLink" title="Red deer">red deer</a> antlers as picks?