The tiny island was decorated with star-spangled bunting Thursday, but some parts remain blocked off, and the main ferry dock was boarded up.
Parks workers greeted visitors with: "We are so glad to see you!"
The visitors said they were impressed.
"It's stunning, it's beautiful," said Elizabeth Bertero, of California's Sonoma County. "They did a great job rebuilding. You don't really notice that anything happened."
Visitors went through security on lower Manhattan after city officials criticized an earlier plan to screen them at neighboring Ellis Island, which endured far worse damage to its infrastructure and won't be open to the public anytime soon. The damage to both islands was $59 million.
In Arizona, sober tributes were planned for 19 firefighters who died this week battling a blaze near Yarnell. Boston prepared to host its first large gathering since the marathon bombing that killed three and injured hundreds, and Philadelphia, Washington and New Orleans planned large holiday concerts.
In Washington, thousands of Americans plan to gather on the National Mall to watch a 17-minute fireworks display and listen to performances by Barry Manilow, Neil Diamond and John Williams conducting music from the movie "Lincoln." New Orleans was hosting the Essence Music Festival stringing stages along the French Quarter. And Philadelphia was hosting what was billed as the "largest free concert in America," with John Mayer, Neo and Hunter Hayes, who was filling in last-minute for a sick Demi Lovato.
Not everyone was welcoming the masses — Hermosa Beach, Calif., was ramping up police patrols and making room in jails for revelers who in recent years have made the city an annual destination for celebrating independence with drunkenness and raucous behavior.