Record-breaking crowd packs Freedom Over Texas, Houston officials say

As we celebrate America's 250th Birthday, the Sons of the American Revolution (SAR) Freedom Chapter is taking center stage.

SAR is a non-profit, male-lineage organization dedicated to preserving the memory of Revolutionary War patriots. SAR members can trace their ancestry back directly. Someone who actively supported the fight for American Independence.

SAR'S mission is to promote patriotism through community activities, youth programs, veterans affairs, and to educate the public and help them understand the freedoms that we have and how we got them.

Their ancestors helped shape America. Today, they are carrying forward the values of freedom and patriotism. Meet the Sons of the American Revolution.

FULL STORY: Sons of the American Revolution celebrate patriotism and heritage

The Sail4th 250 parade has begun in New York City, which is expected to draw large crowds to the city's waterfront.

Many of the participating vessels, known as Class B tall ships, have been arriving in New York Harbor over the past several days.

Saturday's Sail4th 250 parade began at 7 a.m. ET, with ships sailing north on the Hudson River from the Verrazzano-Narrows Bridge to the George Washington Bridge.

Leading that event is America's Tall Ship, the U.S Coast Guard Cutter Eagle.

The larger ships are anchored near Sandy Hook as sailors from 20 nations prepare to sail up the Hudson.

The event is expected to attract thousands of spectators as New York joins the nationwide celebration of the nation's semiquincentennial.

Officials say security checkpoints and screenings will be in place for designated viewing areas during Saturday's Sail4th 250 festivities along the Hudson River.

The Declaration of Independence was signed in Philadelphia in 1776. ABC News' David Muir was in the room where it all happened - and went into the vault holding some of America's founding documents - including the printer's proof of the Declaration of Independence and the first draft of the U.S. Constitution.

Beloved actor, singer and trailblazer Sheryl Lee Ralph delivered a powerful and heartfelt rendition of the Star-Spangled Banner from beside the historic Liberty Bell in Philadelphia to mark America's 250th birthday.