USS Kitty Hawk visits Sydney before being decommissioned

The U.S. Navy's oldest ship in full active service pulled into Sydney Harbor on Thursday for a farewell visit, following its final military exercises before being decommissioned.

The USS Kitty Hawk, which is based in the Japanese port city of Yokosuka, and its crew of more than 5,500 sailors, docked at the Garden Island naval base along with support ships from its battle group.

Thousands of spectators lined foreshores of Australia's biggest city to catch a glimpse of the massive vessel, as half a dozen television helicopters buzzed overhead.

On board, eager American sailors snapped photos and pointed as the white peaks of Australia's iconic Opera House came into view.

The 46-year-old ship - the only U.S. aircraft carrier permanently deployed abroad - recently took part in Talisman Saber exercises off Australia's northeast coast that involved more than 30 ships, more than 100 planes and almost 30,000 U.S. and Australian troops.

The ship's current voyage in the western and central Pacific Ocean was expected to be its last major mission before it is replaced next year by the USS George Washington.

Captain Todd Zecchin said he will mourn the day next year when the USS Kitty Hawk is sent back to the United States to be decommissioned.

"When you're sailing on board a vessel and you go to sea with 5,000 other human beings and you share that entity and that experience, there really is a bond there that can't be broken," he told reporters.

"This is our home and this is our way of life, so when you put her to bed for the last time, it's a big deal and there's a lot of emotion."

Commissioned in 1961, the ship played a key role in the early part of the Vietnam conflict, and was among two carriers in the Persian Gulf that sent planes to launch the Iraq war in 2003.

The diesel-powered ship was deployed to Yokosuka in 1998, and will be replaced with the nuclear-powered George Washington as part of the U.S. military's effort to modernize its forces in East Asia - an area of potential flashpoints with North Korea or China.

The vessel's replacement has sparked a backlash in Japan - the only country to suffer a nuclear attack - where critics oppose the basing of a nuclear-powered warship in domestic waters. Japan's government says the George Washington would boost regional stability.