I see the barbed wire before I see the Amazon logo. Amazon is notoriously secretive about its fulfilment centres, and this one, on the outskirts of the east German city Leipzig, is no exception.
There's very little branding on the outside of the 750,000 square metre warehouse – the size of 11 European football fields – other than a sign saying "amazon.de" and window frames painted yellow.
Inside, after walking past five wall clocks marking the time of Leipzig, Seattle, the UK's Marston Gate, Hyderabad and Beijing, I'm given a fluorescent safety jacket.
"Insist on the Highest Standards" is written on the walls in the room where I am briefed on the rule banning photos. "Our associates [Amazon employees] don't want to be pictured," I'm told.
But I am asked to sign a disclosure form allowing photos of me to be published on Amazon's website, YouTube and Twitter before being warned not to pick up any items in the warehouse – because Amazon's technology system knows exactly where each item is and will notice if they go missing.
The warehouse floor looks like Legoland. Blue and green crates are stacked on grey concrete and the ceiling pipes are painted red. Black crates filled with every household good imaginable – gardening gloves and TV wall mounts, jigsaws and shoes – zoom past on yellow conveyor belts.
The goods are placed in slots on yellow metal shelves before they are packed into cardboard boxes and wrapped with Amazon's branded packing tape in two minutes flat by women dressed casually in T-shirts and trousers.
A plastic "pool float" in the shape of a horse is stuffed into one box with red and yellow paper napkins, while books and coffee beans are packaged together in another.
Unlike some of Amazon's centres (there are 120 around the world), which use robots, this one, which opened in 2016, has plenty of humans.
Around 2000 people are employed, most of them full time, to take items – there are 10 million stored in the warehouse – off shelves in the three tall "Picktowers" each day and put them into crates.
Staff work in two shifts – 6.30am until 3pm, and 3pm until 11.30pm – and staff numbers double temporarily at peak times like Christmas.
There's an "inbound dock" where goods from suppliers come in, and an "outbound dock" where they placed before being packaged and delivered. Turnaround time between orders made on Amazon's website and the despatch of goods is three to four hours if "same day delivery" is requested.
If you live in the nearby city of Berlin and order products before noon, they will be delivered to you by the end of the day by the DHL trucks waiting outside.
Around half of the stock in the warehouse, which is kept at a temperature of around 26 degrees, is owned by Amazon, while the other half is owned by small companies that pay the company to pack and ship their goods. The stock includes goods people have already ordered and those it expects people to order.
Goods are grouped in general categories such as fresh food, books and household products but are then organised by how popular they are. Fidget Spinners – toys for kids – are currently one of the best-selling items.
Crates of Red Bull (and people do order it by the crate) are considered a "high velocity" item and are stored in cardboard boxes next to other fast-selling goods, like vitamins and coffee machines. I see lots of boxes branded with the Philips logo, but can't work out if they contain light bulbs or electronics.
"Low velocity items," like white towels, are stored on the other side of the warehouse. Scannable codes for each item are marked on the floor.
Amazon has nine fulfilment centres in Germany, and the Leipzig centre, which opened in 2016, delivers products all over the world. Some countries, like Poland, operate centres seven days a week but Germans don't like working on Sunday. So online orders made on Sundays for same day delivery in Germany are shipped from Poland.
With Amazon hunting for warehouse space in Australia, analysts and investors are working overtime to understand which retailers will be most affected by the giant's arrival.
On Thursday, Wesfarmers shares dropped 4.6 per cent after a Morgan Stanley report suggested its discount department store chains, Kmart and Target, would be hit harder than specialist chains such JB Hi-Fi, Rebel Sport and Harvey Norman
Germans I meet say they buy lots of goods from Amazon, including alcoholic spirits (which are often on sale), fresh vegetables, wetsuits – which can be returned for free if they don't fit – and DVDs. The Leipzig centre typically dispatches 100,000 boxes a day, but on one particularly busy day 500,000 boxes were put into 100 trucks.
Australian retailers have every reason to be worried.
The reporter visited Amazon's Leipzig fulfilment centre with the assistance of the International Transport Forum
