Last updated: 22 October 2026

Watching a container ship being loaded is one of the most fascinating sights in the modern world. Giant cranes lift boxes weighing up to 30 tonnes on and off a ship in under two minutes each, around the clock. Freighter passengers often get a front-row seat. Here is how it works.

Ship-to-shore cranes

The huge blue, red or white cranes lining a container quay are ship-to-shore (STS) cranes, also called quay cranes or gantry cranes.

• Height: the largest are taller than a 40-storey building when the boom is raised
• Outreach: booms can reach across 24 or more rows of containers on the widest ships
• Lifting capacity: typically 65 tonnes or more under the spreader; some lift two or more containers at once
• Speed: a skilled operator typically makes 25–35 moves per hour
• Remote operation: at many modern terminals, operators work from a control room instead of a cab high above the ship

Ports such as Felixstowe, London Gateway, Southampton and Liverpool use these cranes, and London Gateway is one of the UK’s most automated terminals. Read about freighter travel from the UK to see them from the deck.

The stowage plan

Before a ship arrives, planners create a stowage plan, or bay plan. Every container gets a precise slot identified by:

• Bay: the position along the length of the ship
• Row: the position across the width
• Tier: the height in the stack

The plan balances weight for stability, keeps containers for the next port accessible, separates dangerous goods, and gives refrigerated containers power points.

Step by step: loading a container ship

1. The ship berths, and gangs of lashers and stevedores board.
2. Lashing is removed from containers that are being discharged.
3. Cranes discharge import containers onto trucks or straddle carriers on the quay.
4. Hatch covers are lifted to reach containers stowed below deck.
5. Export containers are loaded in the planned sequence, below deck first.
6. Hatch covers go back on, and deck stacks are loaded on top.
7. Lashing gangs secure the deck stacks with twist locks and lashing bars.
8. The chief officer checks stability, and the ship departs, often within 24–48 hours.

Moving containers around the terminal

• Straddle carriers: tall vehicles that drive over a container and lift it
• Rubber-tyred and rail-mounted gantries: stack containers in yard blocks
• Automated guided vehicles: driverless carriers at advanced terminals
• Terminal tractors: trucks shuttling containers between quay and yard
• Rail terminals: many containers leave the port by train

How fast is it?

A big ship may exchange 4,000–8,000 container moves in one port call, with five or six cranes working at once. That is why freighter passengers sometimes get only a few hours ashore. See life on a container ship.

Watching it as a passenger

From the bridge wings or upper decks you can watch the whole operation safely. Passengers must follow crew instructions and keep out of working areas during cargo operations, because it is a busy and potentially dangerous environment. Many travellers say it is one of the highlights of Frachtschiffreisen.

Frequently asked questions