This photo gives an even better perspective on the size of a Redwood tree. We found a place where we could get almost all of a full grown tree in the picture. I stood beside the tree and Diana took this photo. I wore her red sweatshirt so I would show up against the bark of the tree. Yes, that tiny speck of red at the base of the tree is me. Redwoods can reach 320 feet tall, higher than a 30-story building.