Brenva Glacier
... that when a massive rockfall in 1920 covered part of the Brenva Glacier , it caused it to lengthen considerably, at a time when nearby glaciers were retreating?
... that when a massive rockfall in 1920 covered part of the <b id="mwB18"><a href="./Brenva_Glacier" id="mwB2A" rel="mw:WikiLink" title="Brenva Glacier">Brenva Glacier</a></b> <i id="mwB2E">(pictured)</i>, it caused it to lengthen considerably, at a time when nearby <a href="./Glacier" id="mwB2I" rel="mw:WikiLink" title="Glacier">glaciers</a> were retreating?