SAN DIEGO (CNS) - Around 20,000 revelers are expected Tuesday night in the Gaslamp Quarter for the San Diego Mardi Gras block party.

The annual "Fat Tuesday" event will include entertainment on five stages with headliner Snoopadelic, food and drink specials at more than 20 restaurants and bars in the area, and a New Orleans-style parade with floats along Fifth Avenue.

The event, which benefits the Gaslamp Quarter Historical Society, begins at 5 p.m. and runs until midnight.

General admission tickets cost $40, and VIP tickets -- which include a special entrance, a parade viewing party and other perks -- are $120.

Mardi Gras can trace its roots back thousands of years to pagan celebrations of spring and fertility.

The arrival of Christianity resulted in those festivities being folded into events leading up to Lent, the period between Ash Wednesday and Easter when the faithful would fast or only eat fish. What became known as "Fat Tuesday" in France gave people a chance to gorge themselves of all of their remaining meat, eggs, milk and cheese.

The first Mardi Gras believed to have taken place in the U.S. was organized by French explorers in 1699, in an area just south of New Orleans. New Orleans, or the "Big Easy", is famous for its annual Mardi Gras bash in the French Quarter.