Fast of 17th of Tamuz

All who mourn the destruction of Jerusalem will merit the celebration of her rebirth.
On the 17th of the Jewish month of Tamuz (This year it falls out July 9th 2009) - from the break of dawn until night, as defined by halacha. Jews around the world fast on this day. There are 5 horrible events which occured on that day, one of them was the "Chet Ha'egel" The sin of the golden calf.

Rebbetzin Tzipporah Heller from Naaleh.com speaks about the tragedy that led the Jewish people to the Sin of the golden calf and it's deeper implications.