Glacial erratics, Yosemite National Park

In the Eastern part of the park, there are many granite domes formed by magma pushing close to the crust, cooling under ground into granite, then persisting while all the surface stone is worn away by glaciers and water.

When the glaciers recede, sometimes they leave rather large boulders in rather odd places. What once floated in a river of ice sinks in an ocean of air. So all those pebble like things you see in the foreground are actually rocks the size of living room furniture. Their technical name needs no explanantion.

This is yet another reason why Yosemite is awesome and Teddy Roosevelt was cool.