Well, that young lady is about 5' 7", (just under two meters for you Metric peeps). She's about to walk inside. The trunk was open and rotted enough that you could stretch your hands out, while walking inside and not touch the sides or roof, in parts. At least 3 meters of rot inside, in places. Think about that!
This live tree was even larger than the dead tunnel tree!
Huge, that's about the only way to describe these monster Sequoia trees. Imagine the settlers, who came west, to find these thousand, two, three thousand year old trees. And then, when some went back east, they were never believed. Even when bits we cut off and brought back, the settlers were not believed. Some papers at the time, called it the Great California Tree Hoax!