Americans are celebrating the 228th birthday of the United States.

A special event takes place today where the Declaration of Independence (search) was signed on July 4, 1776. Children descended from the document's signers tap the Liberty Bell in Philadelphia and lead a national ringing of bells. It takes place at two p-m Eastern time.

Other events include the laying of the cornerstone for the 1776-foot Freedom Tower at the site of the Nine-Eleven attacks in New York City (search).

There'll be concerts and fireworks in cities and towns across the country, including those in New York, Washington, D-C, Chicago, Boston and San Francisco.

And of course, Americans will be grilling out, enjoying picnics and joining in a host of down home activities from coast to coast.