Why do you think independence ,missouru, is the starting point for the trail

The trail began at the old Independence Landing north of Independence, Missouri. Here emigrants left steamboats after a five or six day journey from St. Louis. The center of activity in the small town of Independence was the bustling square. Most of the new pioneers camped a mile or two from the square and were busily purchasing supplies needed for their four to five month trek. Those with horses or mules left first so they could feed upon the shorter grasses. The majority with powerful and durable oxen left two weeks later because cattle have a different dentition than horses.