Riverbed in Carmanah Walbran Provincial Park, British Columbia, Canada. Check out the tiny figure standing in front of the center of the tree to get an impression of the size of these trees.
<a href="//commons.wikimedia.org/wiki/User:Ademoor" title="User:Ademoor">Ademoor</a>
CC BY 2.5
<span class="int-own-work" lang="en">Own work</span>