A Covid-19 safety alert sign at the Olmsted Island Overlook on the Maryland side of Great Falls of the Potomac River. "Masks are required outdoors when social distancing cannot be maintained."
<a href="//commons.wikimedia.org/wiki/User:Lorax" title="User:Lorax">G. Edward Johnson</a>
CC BY 4.0
<span class="int-own-work" lang="en">Own work</span>