Anthem of the Seas and 5 other colossal cruise ships

The Anthem of the Seas arrived in downtown Halifax Thursday morning under grey skies, casting an impressive figure on the historic waterfront. Scroll down to take a look at the massive cruise liner, along with five other enormous ships that can be more like small towns on water.

Ship expected to set port record in Halifax. 

Officials say the Royal Caribbean Cruise Lines ship has a capacity of 4,900 passengers and weighs more than 152,194 tonnes, making it the fifth largest cruise liner in the world. It's expected that the capacity, along with crew, will set a new port record for the highest number of cruise guests on a single vessel. 

More than 2,000 staterooms. 

The quantum class ship has everything from bumper cars and roller skating to a circus school and four swimming pools, along with more than 2,000 staterooms.

Crystal Serenity brings new era of tourism to Canada's Arctic.

Earlier this week, the 280-metre long Crystal Serenity entered the fabled but dangerous Northwest Passage and arrived at the hamlet of Cambridge Bay, Nunavut. While not among the world's largest cruise ships, the Crystal Serenity is the largest vessel to ever attempt to go through the passage and has a capacity of about 1,600 passengers and crew, more than the entire population of Cambridge Bay.

The world's largest cruise ship.

Harmony of the Seas is 361 metres long and weighs more than 205,000 tonnes, making it the biggest cruise liner in the world. Launched earlier this year, the ship can hold 5,479 passengers and 2,100 crew and contains everything from rock climbing walls to a skating rink to huge water slides.

Allure of the Seas.

Prior to the 2016 launch of Harmony, the Allure of the Seas took the title of the world's largest cruise ship, weighing in at more than 204,330 tonnes with a capacity for 5,492 passengers and 2,384 crew. 

The atrium on the Allure of the Seas shows row upon row of rooms. Every cabin has an iPod dock. 

An ocean oasis.

Oasis of the Seas has been bumped from second place to third on the list of world's largest cruise ships. Oasis was reportedly the first vessel of its kind to offer zip-lining when it was launched in the fall of 2009.

World's first 'smart ship.'

Quantum of the Seas, launched in November 2014, was billed as the world's first smart ship and the most high-tech cruise liner in the world. 

Rooms that are windowless have "virtual balconies." The ship has an observation pod attached to a mechanical arm that carries passengers over the edge of the vessel, 100 metres above the sea.