A U.S. Coast &amp; Geodetic Survey (now <a href="https://en.wikipedia.org/wiki/U.S._National_Geodetic_Survey" class="extiw" title="w:U.S. National Geodetic Survey">NGS</a>) benchmark on the old City Hall building in <a href="https://en.wikipedia.org/wiki/Tampa,_Florida" class="extiw" title="w:Tampa, Florida">Tampa, Florida</a>. The crossed lines at the center of the disk mark an altitude of 19.511 feet above mean sea level. The disk is stamped with the year in which it was set (1932).
<a href="//commons.wikimedia.org/wiki/User:Ebyabe" title="User:Ebyabe">Ebyabe</a>
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<span class="int-own-work" lang="en">Own work</span>