Seven seems to be an important number in many religions. Seven may be significant because there are seven visible celestial bodies that wander across the sky, the Sun, Moon, and the five planets visible to the naked eye, Mercury, Venus, Mars, Jupiter and Saturn. Because they are all wanders we can call them planets, even though today we normally do not think of the Sun and Moon as planets. Chariots were developed before 3000 B.C. and offered a warrior a stable platform from which to shot arrows and cast spears at his enemies. It is not surprizing that the people who wrote the Rig Veda recognized of the more powerful gods, Surya, as having two of their most powerful weapons of war, the horse and chariot.
Today there are a great number of temples in India devoted to Surya.
The 15th century Surya temple at Ranakpur, Rajasthan. Many of the temples are easily recognized because they are often decorated with carved images of Surya, who is shown holding two daisy shaped objects, one in each hand, and accompanied by images of horses. Often there are also one or more carved images of a chariot wheel decorating the Surya temples. In some cases there are seven gods, representing the planets, shown in association with chariot wheels. Rear of Surya temple, Ranakpur.