Summer Solstice
It can fall on June 20 and June 22 in the Northern Hemisphere and between December 20 and December 23 in the Southern.
The summer solstice, also known as estival solstice or midsummer, occurs when one of the Earth's poles has its maximum tilt toward the Sun. It happens twice yearly, once in each hemisphere. Wikipedia
I view the summer solstice as a time for transition and growth. This time from Maiden to Mother. It is just the spark as we begin to mature and take those first steps into thinking of motherhood be it through children or nurturing ideas.
This is a festival about love and fertility.
I like to imagine the idea of "manifest" on this day. It is making things real, tangible. Reaching out and touching the Earth. Building that foundation and grounding your energy and being.