A very rare Junkers F-13 in airworthy condition.
This airplane, which maid flight was in 1919, is the very first airplane with stressed-skin.
<a href="//commons.wikimedia.org/wiki/User:Tibboh" title="User:Tibboh">Tibboh</a>
CC BY-SA 4.0
<span class="int-own-work" lang="en">Own work</span>