4. Oklahoma
Horse Population: 320,173
Horses per square mile: 8.0
Number of People/Horses: 12.9
The horse industry in Oklahoma is one of the oldest in the country. The Oklahoma inhabitants started relying on horses since the beginning of the 18th century. But now as you can imagine, the industry has grown out of mere farm-work and traveling. Oklahoma hosts several horse-related shows and expos of the national and international level every year. Oklahoma horse industry is quite big and is growing rapidly. As is evident by the numbers given above.