Preseli to Stonehenge: What and when is the summer solstice?

The event is marked with the Summer Solstice whereby we receive the greatest amount of sunlight in the day, some 16 and a half hours. After this point, the amount of sunlight begins to reduce on a very, very small basis. 

Equally, on December 21, there is the other end of the equation, with the Winter Solstice and fewer than 8 hours of daylight.

Because the Earth is tilted by approximately 23.4 degrees, the amount of sunlight in both the northern and southern hemisphere varies. 

The Earth's journey around the Sun generates the seasons and in turn the amount of daylight we receive with the planet accordingly either tilted toward or away from the Sun. 

When the northern hemisphere is at its greatest tilt towards the Sun, the Summer Solstice is duly marked, with all other days following this point now beginning to gradually see a shortening of daylight. 

Côr y Cewri, also known as Stonehenge. Photo: PA

Whilst the landmark Côr y Cewri or Stonehenge is often seen as one particular place where the Summer Solstice is marked (along with other similar events), the stones at Stonehenge are believed to have originated from a site in Wales -  Waun Mawn near the Pembrokeshire coast.

It is believed that around 3200 BCE, farmers in the Preseli Hills built a great monument, the stones of which were placed in a circle aligned with the Sun. 

The purpose of the construction remains a debate, but research in 2017 and 2018 led by University College London archaeologist Michael Parker Pearson suggests that many of giant stones - bluestone - were later moved by the farmer's descendants some 200 kilometres to Salisbury Plain in Wiltshire, to create Stonehenge.

As the northern hemisphere marks the Summer Solstice, it's also of note that our counterparts in the southern hemisphere mark their shortest day of the year, before December marks the reverse for both hemispheres.