2025 Summer Calendar Schedule Calendar Dates. The 2025 north america race season is upon us and many exciting events are open for registration. The academic year is divided into winter semester and summer semester.

We have an online calendar that will help you locate the day and date of a specific holiday. Summer 2025 starts on friday, june 20th in the northern hemisphere, with the first day of summer being the longest daylight day of the year with the earth’s axis having reached its furthest tilt and begins to change directiion back.