It's one of the world's oldest, most vital, most taken for granted industries. Without ships,

90% of everything we use or consume would never reach us. Through wars, plagues and storms,

the world's 100,000 cargo vessels sail on grain and steel carriers, oil tankers, container ships,

dependent on the 1.7 million seafarers who crew them and on layers of unseen networks that

also keep them afloat, charterers, brokers, insurers, chandlers. It's a world that's eternal

and yet continually changing visible to all of the surface and yet deeply at peak underneath.

I'm Tim Hewall here on the BBC World Service and this is part one of deep waters, the hidden world of global shipping.

It's immediately in front of me here on the breakwater in the port of Samson in Northern Turkey,

on the Black Sea coast of Turkey. It's a huge grain carrier, it's got a black hole, white cabins above

and towering over it is a sky blue crane. Everything here I should say is in winter sunshine,

everything is in bright primary colours. Lories are coming onto the breakwater, they each have two rows

of huge plastic sacks of flour, almost as tall as the person, 30 of these on each truck

and the crane is lowering down a bright orange steel bar that has ropes kind of ties coming down from it

and it's just coming down now. There's five people here in yellow hard hats, they're climbing up now onto the lorry

and they're going to tie these cords, I suppose, onto each one of these brilliant white plastic sacks of flour.

The ship, I mean this is a typical bulk carrier, it's some nearly 25,000 tons dead weight, the MC rider,

it's flagged in Barbados, so on the edge it says a rider, Bridgetown the capital of Barbados

and all this then is being loaded, it's Ukrainian origin wheat milled into flour here in the Turkish mill

in the port of Sampson here and it's part of the World Food Programme Humanitarian grain initiative.

We're going to climb up the Gangbank now and we're now looking down into the hold, this is a massive hole

so these kind of fat white sacks, there's another big bar of 30 more dangling now above our head

and gradually coming down right past us as we look here from the top of the hold, gradually coming down into position

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