For people that live in the Northern Hemisphere, Saturday, June 21st, will appear to be one of those glorious days when the sun has forgotten to set and depending on where they live, that may actually be true. That's because tomorrow is not just the first day of summer, but also, the longest day of the year.

Also known as the summer 'solstice' - a Latin word for 'sun stands still', it is the day when the Earth's axis is most inclined toward the sun. Countries in the Southern Hemisphere experience a similar phenomenon, except in reverse order - On June 21st, they will welcome the first day of winter and therefore experience the shortest day of the year.

The length of the day depends on the location of the city or town. Washington D.C. on the east coast of United States will receive almost 15 hours of sunshine, while the islands of Hawaii in the southwest corner of the country, will have to settle for just a tad over 13. Head over to Europe and you will be able to soak in over 18 hours of sunshine in London or more than 21 hours in Stockholm. Want more? Than your best bet is the Arctic Circle where the sun will literally stand still for the full 24 hours! Meanwhile, the residents of the Antarctica or South Pole will be completely shrouded in darkness!

While we now know the reason behind this extended day or night, people that lived hundreds of years ago were not privy to the same knowledge. They therefore regarded the extra daylight hours as a sign that the sun had not abandoned them and celebrated the news with joyous rituals. Fortunately, some of them continue till this day.

One of the oldest and biggest events is held at Stonehenge in Wiltshire, England where thousands of people gather each year, to pay homage to the rising sun. In the Polish city of Poznan, St. Jones Night as it is called, is celebrated with the release of thousands of candle-lit paper lanterns that are adorned with personal messages from their creators. Japan's 'candle nights' puts a modern-day twist on the occasion. Started in 2003, the environmentally friendly celebration urges residents to turn off all lights and electrical devices from 8.00pm to 10.00pm, for an entire fortnight.

The beautiful coastal city of Santa Barbara in California, hosts a three-day Summer Solstice Festival complete with parades that feature extravagant floats, whimsical costumes and creatively choreographed dancing ensembles. New Yorkers celebrate the day by showing off their 'downward dogs', at the 'Mind over Madness Yoga' celebration held in the middle of the city's bustling Times Square, while San Franciscans take advantage of the daylight with storytelling and bonfire celebrations at the city's numerous beaches. Does your town or city have a fun summer solstice ritual? if so, be sure to tell us all about it, by adding your comments below.

Resources: Washingtonpost.com,wikipedia.org, huffingtonpost.com, ibtimes.com