Summer solstice begins in the northern hemisphere on or around June 20th or 21st, when the north pole is at its maximum tilt toward the sun. That means the sun has reached its highest point in the sky all year, making it the longest day with sunlight of the year. This daylight will last a little more than 15 hours, while in the southern hemisphere, it is the winter solstice, their day with the shortest amount of light.
Welcome summer by going outside to play, begin early and stay out late. Drink a lot of water and wear sunscreen. Appreciate the mountains, lakes, deserts, or oceans while enjoying the flowers, bugs, or whatever it is that you love.