Americans Stage Party on Country’s Birthday : Holiday: Millions enjoy traditional activities on a hot Fourth of July. Former President Jimmy Carter and ex-hostage Frank Reed are both honored.

Former President Jimmy Carter received the city’s Liberty Medal in a patriotic celebration Wednesday, reminding Americans that human rights are key elements in the fabric of the nation.

Carter was warmly welcomed by a crowd of 10,000 as he was awarded the bronze medal in front of Independence Hall, where the Declaration of Independence was signed exactly 214 years ago. The award also comes with a $100,000 prize.

At a news conference, Carter said he opposed a constitutional amendment against flag burning.

“I don’t think that anybody should burn the flag,” said Carter, an ex-Navy man. “But we should not amend the Constitution to guarantee its protection.”

Carter was honored for his work to promote liberty and human rights since leaving office in 1981.

Last year, Polish Solidarity leader Lech Walesa was the first person given the honor.

Also in Philadelphia, “America’s Birthday Cake,” big enough to serve 25,000 people, was cut. Elsewhere, Americans turned out by the millions Wednesday to celebrate the birth of their nation.

American flags, always in abundance on Independence Day, were an especially hot item this year. Flag merchants in New York and a small-town Louisiana mayor said the flag-burning issue had made showing the flag more popular.

“It’s been a banner year, and that’s not just a flag company joke,” said Steve Sevits, vice president of sales for the Uneeda Flag company near Albany, N.Y.

Spectators braved the baking sidewalks of Chicago’s Michigan Avenue to watch a four-hour Shriners parade.

It was hot, hot, hot almost everywhere. Baltimore sizzled at 100 degrees, and New York burned, where at 92 degrees it was the hottest day of the year as 800,000 people headed for the beach at Coney Island. It was 105 degrees in Enid, Okla.

High-temperature records for the date were snapped in Erie, Pa., where it was 97 degrees, Syracuse, N.Y. (95) and Alpena, Mich. (93), and tied in five other cities in the East and Midwest.

It wasn’t all fun, fireworks and parades. The Veterans of Foreign Wars, the Paralyzed Veterans of America and AMVETS organized a midday rally in a park in St. Petersburg, Fla., to push for better health benefits.

At least 2,000 veterans, many in uniforms bedecked with campaign ribbons and carrying flags or wearing flag-lapel pins, attended.

At the Spirit of America Festival in Decatur, Ala., former hostage Frank H. Reed, who was released in April after 44 months of captivity in Lebanon, received the annual Audie Murphy Patriotism Award.

In Washington, D.C., spectators on the Mall between the White House and the Capitol were entertained by musical performances. A free concert at the Capitol was planned for the evening by the National Symphony Orchestra, followed by a fireworks display at the Washington Monument.

Nearby, Luther Place Church, a few blocks from the White House, staged a Fourth of July cookout for the homeless who live in a complex of group homes and shelters in the area.

LOCAL OBSERVANCES: B1