Y Sap mine
... that the Y Sap mine was an explosive planted under German trenches before the Battle of the Somme in World War I?
... that the <b id="mwCBo"><a href="./Y_Sap_mine" id="mwCBs" rel="mw:WikiLink" title="Y Sap mine">Y Sap mine</a></b> was an explosive planted under German trenches before the <a href="./Battle_of_the_Somme" id="mwCBw" rel="mw:WikiLink" title="Battle of the Somme">Battle of the Somme</a> in World War I?