The National Institutes of Health, Bethesda, MD, USA.  A bad photo, I know; but it's the only aerial thus far on Wikipedia.  Feel free to speedy delete if a better version is uploaded.
<a href="//commons.wikimedia.org/wiki/User:Thisisbossi" title="User:Thisisbossi">Andrew Bossi</a>
CC BY-SA 2.5
<span class="int-own-work" lang="en">Own work</span>