I have quoted Donna Henes' book Celestially Auspicious Occasions before, and I will do so again, because I think she says it so well:
The seasonal ascent of light and temperature is not -- despite popular belief -- due to our distance from the sun, but to the degree of directness of its rays. It would be logical... to assume that in the summer the earth approaches closest to the sun, and that we are farthest away in the cold dark of winter. Wrong! The earth reaches its perihelion, the point on our orbit that brings us closest to the sum, in winter (usually around Jan 2 or 3); and conversely, during summer (July 5 or so) we attain our aphelion, the farthest reach of our range from the sun.
Though the distance from the sun is greatest in the summer, it is at the Summer Solstice that the sun sits highest in the sky. The steep path of its rays is angled vertically overhead. Its energy is aimed arrowlike straight down on us.
The Summer Solstice is the height of the glory of the season of the sun. It is at this point that the dark must begin to creep back.... For several days before beginning its descent, the sun stands sentinel at dawn. It seems to stand stark still in the sky, which is what solstice means: "sun stands still". (Just) As we celebrate the birth of the brand-new sun at the Winter Solstice, we
salute its vibrant maturity at the solstice in the summer.
In megalithic times, people began to create structures that would enable them to track the course of the sun, the source of life. These solar observatories were specifically designed to give precise determination of the days of the solstices... that are the times of greatest extreme. It was necessary to calculate the longest summer day, since it serves as a signal light, a warning sign for changes in light and weather to come.
Indigenous Europeans... built many such sun shrines. Stonehenge, the most famous standing stone circle, has its main axis in perfect alignment with the Summer Solstice sunrise. Strikingly similar monuments to the movements of the heavens were built by the ancestors of the tribes of the Great Plains of the northern US and Canada... positioned in exact orientation to the solstice sunrise. There are more than 50 knowing medicine wheels, some dating back 2,500 years.
Summer Solstice is a holyday celebrated with fire and flame. Bonfires are lit in honor of the sun, perhaps the most universal of the celebrations. It is the ultimate act of flattery by imitation.... And at the same time, the light and heat of the fire serve to soothe and affirm that, though departing, the sun will surely return.
In ancient Egypt, the Summer Solstice was celebrated by the Burning of the Lamps in honor of Isis, Queen of Heaven. In Rome, the day was dedicated to Vesta, known as Hestia in Greece... guardians of the public hearth and altar. The Norse goddess Sol, Sul, or Sulis drove the chariot of the sun. Ancient Buddhist texts speak of the sun chariot as the Great Vehicle or the Chariot of Fire. The ancient Greeks pictured the Sun carried across the daytime sky in a golden chariot steered by Apollo (Artemis' twin brother; she was goddess of the Moon and the hunt).
The Hopi Summer Solstice ceremony perfectly describes this seasonal shift in terms of a transferal of our spiritual reliance on divine illumination to the realization of our own personal response-ability.