At 1:16 EDT today, summer officially starts here in Boston as well as the Northern Hemisphere.

The first day of summer is also the summer solstice, which occurs when the Earth’s axial tilt is in such a position that it receives the most amount of sunlight. (wiki.)  Basically the Northern Hemisphere leans closest to the sun resulting in the longest day and shortest night of the year.

To celebrate the first day of summer, join the Friends of Copley Square for their second annual Summer Solstice Stroll or take advantage of Free Ferry Day and head to the Boston Harbor Islands.