The main objective of the circulatory system is  transporting oxygenated (rich saturation of oxygen) blood around  the body. The de-oxygenated blood enters through the vena cava and  into the right atrium of the heart. It then goes to the right  ventricle, directly below the atrium.
Pyramid of the Sun. Less than half a mile south of the Pyramid of the Moon is the Pyramid of Sun. At a height of more than 200 feet (63 meters) and a base more than 730 feet (225 meters) long on each side, this pyramid is one of the largest structures created in the pre-Columbian New World. It would have been completed around 200 AD.
When the Great Pyramid was first built it was 145.75 meters high (481 feet.) It used to be the tallest structure in the world for more than 43 centuries. If it hadn't lost 10 meters (30 feet) off the top over the years, we might have seen King Kong climbing this tomb instead of the Empire State Building.