From the Collins African Wildlife guide:
Imagine a creature as big as a truck, with a nose as long as its legs, that functions as a siphon, snorkel (on deep water crossings), squirt-gun, trumpet, and feeding tool powerful enough to rip branches from trees but delicate enough, with finger-like projections at the tip, to pick up a pea.
Elephants can be seen at most of the parks and you’ll normally find them near watering holes and around trees. Tarangire offers the best place to see large herds of elephants, and in Ngorongoro Crater you will see only the large bulls with their massive tusks. Most elephant herds are females while males stay in bachelor groups or alone.
Sometimes you’ll turn a corner and find them blocking the road, in which case, you’ll just have to sit and wait until they move. Another bit of advice, be sure not to get in-between a mother and her child.