Sydney Harbour was the scene of a cruise ship gridlock on Thursday night after a medical emergency brought the MS Amsterdam to a standstill.
The 237 metre-long luxury vessel came to a stop near Manly harbour about 7pm to offload a male passenger in his 50s who had suffered an undisclosed medical episode.
The NSW Police marine area command responded to a call for help from the ship's personnel.
Water police collected the sick passenger by boat and took him to Watsons Bay, where paramedics treated him before taking him to hospital.
The cove was soon crowded with maritime activity as two Sydney ferries, Freshwater and Collaroy, slowed to make room for the stalled cruise ship.
A second cruise ship, Explorer of the Seas, soon entered the fray. The 311 metre-long Explorer, with its 15 decks, dwarfed the Amsterdam and it squeezed past the stalled ship on its way through the Sydney Heads and out to sea.
A spokesman for the Australian Maritime Safety Authority said it had not received a distress signal from the Amsterdam, suggesting the medical emergency was not a major incident.
The Amsterdam was still stationary at 8pm, switching on its lights in the dusk.
It was soon on its way, with sea-scanner.com logging the vessel about 30 kilometres north-east of Sydney by 9.30pm en route to Mooloolaba, Queensland.
Owned and operated by Holland America Line, the $US400 million vessel sails around Asia, Australia, New Zealand and the South Pacific during the southern hemisphere summer. In winter the Amsterdam makes its way to Alaska.