All present and correct: Santa’s other little helpers - at Amazon

As the busiest online shopping day of the year approaches, we take a look round Amazon’s giant depot

It is rather like entering the domain of a very neat but eccentric shopkeeper. In one section, Ninjago Lego boxes sit next to phones and cushions while in another, a dinner set shares space with a paper trimmer, princess bed guard and floor sander.

To the outsider, it is baffling. To the people that work in this Aladdin’s cave just over the Forth Bridge, the operation runs like clockwork – digital clockwork that is.

This is Amazon’s distribution warehouse, or “fulfilment centre” as it is known (Amazon being a company born in the US). It is a place which will soon be responsible for making countless Christmas dreams come true.

From its origins as an internet bookseller, Amazon has grown into the world’s largest online store which, together with third-party sellers, offers millions of new, refurbished and used items in categories from baby and pet supplies, to jewellery and gardening goods.

Sandy Davidson, general manager of the Dunfermline centre, who is conducting the tour puts it simply.

“We want to be the place you can find and buy anything online,” he says.

Covering a site of one million square feet – equivalent to 14 football pitches – the Fife centre is cavernous. The sense of space is amplified by the fact that in large sections of the three main halls, empty ceiling-high shelves still await Christmas orders.

On an average day, around 100 lorries will unload goods at the centre, including items already ordered by customers, those sent in by third parties for storage, and Amazon’s own stock.

At peak times, Amazon.co.uk will take orders for more than three million items in one day and a full lorry will leave one of its eight UK fulfilment centres every two minutes and 45 seconds, shifting 1124 tonnes of goods.

The centre is currently gearing up for what is traditionally the busiest online shopping day of the year, nicknamed Cyber Monday, which falls on the first Monday of December.

This is an American marketing term for the Monday following the Thanksgiving holiday weekend in the US and was created by companies to persuade people to do their Christmas shopping online. With the Christmas rush yet to begin, however, the Dunfermline centre is currently an oasis of calm.

Goods unloaded from lorries parked at the 22 bays are checked and sorted according to size and product type before being handed over to a team of “receivers” whose job it is to scan them into the system.

Larger items such as TVs, inflatable mattresses and vacuum cleaners, are stored in their boxes on shelves in Hall Three. Smaller items are divided up, placed in yellow crates known as totes and stored in Hall One. Here a newly-built “pick tower”, several storeys high, is lined with aisles containing shelves or “bins” loaded with goods.

Each aisle is the responsibility of a “stower” – the person who collects the totes from the conveyor belt and stacks the goods on the shelves. Each tote, product and bin contains a barcode which is scanned to ensure the new location of each product is recorded in the system.

Rather than being stored in the same section, each Harry Potter film will be placed in completely different locations, and Edinburgh editions of the board game Monopoly will be kept apart from the London edition.

This apparent randomness is part of the Amazon stock-keeping system designed to reduce human error when it comes to collecting goods for an order.

This part of the process is carried out by “pickers” who are given a shopping list of items to collect for around 40 different orders. Handheld scanners act as sat navs providing them with the shortest route to follow in order to collect all the products on their list.

The fact that similar items are stored in completely different locations prevents them accidently picking up the wrong product. Similarly, popular items will be stored in several locations, avoiding the scenario where several pickers converge on one place at the same time.

Which only leaves the question of what the biggest sellers will be this Christmas. At the moment they are expected to be the new Kindle fire tablet along with the cookbook Jamie’s 15-Minute Meals, and the latest Furby toy.

Just spare a thought for the person who has to find it.