At the time of the summer solstice, Earth is at a point in its orbit where one hemisphere is most tilted towards the sun, causing the sun to appear at 23.45 degrees above the celestial equator, thus making its highest path across the sky. The summer solstice is the day of the year with the longest daylight period and hence the shortest night.Summer Solstice is one of the days celebrated by some during the year to mark the turning of the seasons, along with Samhain, Winter Solstice, etc. Celebrations held on or near the solstice include: the ancient Celts' Alban Heruin ("Light of the Shore"); the celebration of the earth, the feminine, and the yin forces in ancient China; the feast day of St. John the Baptist by Christians (June 24); and simply Midsummer in many traditions. The day is termed Litha by some neopagan groups, and there are celebrations held at Stonehenge.
The first illustration (above left) for this post comes from Cassandra Eason's The Druidic Year, while the second illustration (at right) is a painting by Jane Brideson (available as a greeting card from 13 Moons, and perhaps others).
Do you see the honeycomb included in the image? Again according to ReligiousTolerance.org, "The first (or only) full moon in June is called the Honey Moon. Tradition holds that this is the best time to harvest honey from the hives." (Here's a list of moon names, for those of you who, like me, are fascinated by such lists. *grin*)