Kayaker surfing a <a href="https://en.wikipedia.org/wiki/Standing_wave" class="extiw" title="en:Standing wave">standing wave</a> in <a href="https://en.wikipedia.org/wiki/Great_Falls_National_Park" class="extiw" title="en:Great Falls National Park">Great Falls National Park</a>.
<a href="//commons.wikimedia.org/wiki/User:Jarekt" title="User:Jarekt">Jarek Tuszyński</a>
CC BY-SA 4.0
<span class="int-own-work" lang="en">Own work</span>