Lock 71. This is the upstream most of the composite locks, so note the rough stonework which was normally covered with wood to protect the boats. 
HABS says: 1. GENERAL VIEW OF LOCK LOOKING NORTH - Chesapeake &amp; Ohio Canal, Lock 71, 167.0 miles above tidewater, Oldtown, Allegany County, MD
<bdi><a href="https://en.wikipedia.org/wiki/en:Jack_Boucher" class="extiw" title="w:en:Jack Boucher"><span title="American photographer">Jack Boucher</span></a>
</bdi>
1960-02
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