The Seven Seas defined the ancient world. I wanted to see how millennia of human interaction had affected them, and how MPAs – essentially ‘national parks’ in the seas – might protect them.

Mediterranean Sea

2014 | 43°N 7°E
10 km: 3 hrs 33 mins

Water temperature: 25°C

I was struck by the colour of the water; the Mediterranean Sea is an incredible blue. From the surface you can’t tell that this is one of the world’s most overfished seas, with a staggering 95% of its bottom sea fish endangered.

World free-diving champion Pierre Frolla accompanied me on this 10-kilometre swim from Monaco – the first on our Seven Seas expedition. As a local dive instructor, Pierre has witnessed first hand the damage that happens when visiting cruise ships drop anchor here; the anchors drag along the seabed, ripping the coral to shreds and leaving scars on the sea floor. Without healthy coral, an ocean ecosystem can’t support fish recovery; combine this with overfishing and you understand why the underwater world here looks more like a desert than a garden.

According to the WWF Living Planet Report of 2014, 52% of the world’s wildlife has been lost in the past 40 years – that’s within Pierre and my lifetime. This devastation is happening on our watch. I’m thankful that Prince Albert of Monaco is a dedicated champion of Marine Protected Areas: 100% of the seas of the principality have been declared protected.

That might seem like a drop in the ocean, but it means everything to a fish looking for a home.

Adriatic Sea

2014 | 44°N 15°E
10 km: 3 hrs 55 mins

Water temperature: 26°C

Perspective is everything. I was reminded of this in the middle of the second of our seven swims, through the Adriatic Sea. We were making our way along the beautiful Dalmatian coast, in a Marine Protected Area outside the ancient city of Zadar. Again I was swimming 10 kilometres, this time accompanied by hard-working photographer, Kelvin Trautman.

I think Kelvin ended up doing a lot more swimming than I did – and he was lugging his camera in its underwater housing! He would swim ahead of me, focus his lens, dive down to get an underwater angle, come back up to check he’d got the shots, then sprint ahead to get in front of me again. He did this for about seven kilometres of the swim. Then he saw a cliff that provided a wonderful opportunity to gain a new perspective on what we were doing.

So he climbed out of the water, ran up to the top of the cliff, took pictures from up there – directing me all the time – sprinted back down, and jumped back in the water to carry on with the swim.

Kelvin understands what it means to take an iconic picture – the kind that tells a story so succinctly that you don’t need a caption. He took one from that cliff that shows me way down below, a very little human in the middle of a very big sea. It’s all about perspective.

We ended that swim near a tuna farm, and took more pictures of their huge underwater nets. There were hundreds of tuna circling around inside, like powerful little torpedoes. I learned that it takes 10kg of mackerel and sardines to produce 1kg of tuna; this effectively means that those tuna are feeding the rich, who can afford expensive fish, and not feeding the hungry, who would happily eat sardines.

I had to ask myself: have we lost our perspective?

Aegean Sea

2014 | 37°N 23°E
10 km: 3 hrs 12 mins

Water temperature: 27°C


A good boat can be hard to find. Our arrival in the shipping metropolis of Piraeus fell on a Greek public holiday, so we knew we’d have trouble finding a support vessel for our Aegean swim. Luckily Paul Gripari was about to embark on a swim to raise money to help WWF’s campaign to save the threatened Mediterranean Monk Seal. He said he’d like to come along to see how we did things on our swim. He also had a boat that we could use.

That was an understatement – it turned out that Paul owns a fleet of 18 ships. Some 90% of the world’s trade still travels by ship, so when you speak to a ship owner you also get some understanding of our global consumption “needs”, and the challenges modern shipping faces to meet them.

Paul and I were both shocked to see the state of the sea floor as we swam. Directly underneath us there were cans and bottles, tyres and plastic bags, even old shoes. No sea life, just trash as far as visibility allowed us to see.

Although we were close to one of the biggest container ports in Europe, shipping was not directly to blame for the state of the seabed. Ships are just a measure of how much we consume, and how quick we are to carelessly discard our stuff. Too many of the things we throw away on land come down rivers or blow off the shore and end up in our seas and oceans.

Responsible ship owners welcome measures to reduce their impact on the oceans, even when it affects their bottom line. Paul told me about the water treatment systems that ships are now fitted with to keep ballast water from transporting alien species between regions. Our next stop would be the Black Sea, where I would come face to face with why this is so vitally necessary.

Black Sea

2014 | 43°N 34°E
10 km: 2 hrs 48 mins

Water temperature: 27°C

Swimming though millions of jellyfish is a surreal experience. The ones we encountered in the Black Sea and the Bosphorus glowed green and blue, like neon lanterns in the water. So beautiful – but so wrong.

The Mnemiopsis, or ‘sea walnut’, comes from the Atlantic, thousands of kilometres from the Turkish coastal waters where we were doing the fourth swim. They were brought here in the ballast water of ships arriving from the east coast of America.

I’m always pleased to sea living creatures thriving in the water, but I knew that this Mnemiopsis bloom meant an ecosystem out of balance. They are voracious eaters of zooplankton and fish larvae – and they’re particularly fond of anchovy eggs; now that local food staple is under pressure.

Turkish patriotism is extraordinary, and their enthusiasm for our swim was too. A team of Turkish triathletes pitched up to join me in the water, even though the conditions were horrendous. The sea was so turbulent that its surface was frothy. I would never ordinarily swim in those conditions, but our schedule was tight, and we only had one available day to do the Black Sea swim.

It was rough going. At one stage I spent ten full minutes swimming as hard as I could, and stayed in one spot! The team considered pulling me out, but I finally caught a current and pushed through. That relief came too late for most of the triathletes who all pulled out – with the exception of Baras Kazanci. Baras stayed with me to the end. He wasn’t just committed, he was fast! We had a great time racing.

Red Sea

2014 | 29°N 34°E
10 km: 2 hrs 57 mins

Water temperature: 32°C


“Mad dogs and Englishmen go out in the noonday sun.” That song ran through my head as we waited for the start of my Red Sea swim. The temperature in Aqaba was 55°C (131°F) – in the dry desert that feels like standing underneath an industrial hair drier for fun. I was longing to get into the water, but I’d been asked to do a speech before the start of the swim, and the only time local officials – including Jordan’s Minister of the Environment – could fit me into their schedule was 11a.m. By the time the formalities were over, it would be midday. But since the King of Jordan himself had been kind enough to lend us a support boat, we needed to say a proper thank you.

By the time we set off the sun was scorching, and no amount of sun-tan lotion was going to stop us getting completely frazzled! That didn’t put off the local swim team who swam along with me. A lot of the kids had goggles and flippers – all the better to enjoy the exquisite coral when we swam through the Marine Protected Area. The coral colours were amazing, orange, yellow and red – and a beautiful blue coral surrounded by tropical fish.But as soon as we left the Marine Protected Area, the coral was grey and dead, the fish all gone.

Just before I jumped into the water I’d asked the boat’s skipper whether I should keep a look out for sharks. He told me not to worry – they were fished out long ago. I supposed he was trying to comfort me, but all he did was bring home the reason we were doing these swims: to urge for more Marine Protected Areas to create environments where sharks can thrive. As apex predators, sharks are indicators of a healthy marine ecosystem.

If you see a fin cutting through the water, you should feel a thrill. But it should be the thrill of celebration, rather than fear.

Arabian Sea

2014 | 22°N 59°E
10 km: 3 hrs 15 mins

Water temperature: 16°C


It’s not fair to have favourites, but our Arabian swim stood out for me. Maybe because it was the penultimate one before we headed back up north. Or maybe it had something to do with mythical stories and Arabian nights.

We were going to set off from Ras al Hadd, where the Gulf of Oman meets the Arabian Sea. There were plenty of tales about this wild outpost with its lonely lighthouse – including the legend that a starving shipwreck crew once ate the lighthouse keeper! An old friend and master mariner told me that when they sailed here they called it “Razzle Dazzle”, because you can see the lighthouse from miles away.

We arrived late at night with a problem; we didn’t have a pilot for our expedition, and we needed someone with knowledge of local waters to steer us. But I walked through a small village and met a fisherman tending his nets. His name was Rabi, an old man with years of salt-water adventures etched into his skin. We couldn’t speak each other’s languages, but he indicated with a nod that he would do the job. I can honestly say that in all my years on the water, I have never seen someone so at one with his craft. I wished I could understand the sea stories he must have to tell.

I forgot all about stories when we swam into a shoal of endangered Green Turtles. Green Turtles are not literally green – their patterns are more like those of a giraffe. Now there were dozens and dozens of them all around and underneath me, flipping gently through the water. To see so many here, near the beaches where they lay their eggs, was wonderful. But I couldn’t help but think of the Hawksbill Turtles, which are even more threatened in these waters. I wanted to ask our pilot when he had last seen one of those, but he was staring out at the horizon, lost in his own thoughts.

North Sea

2014 | 51°N 0°E
60 km: 6 hrs 22 mins

Water temperature: 17°C

After all the helping hands we had along the way, I didn’t expect to have to do battle with an adversary on the home stretch. But the last of our seven swims would prove to be the most logistically challenging.

We planned to end our swim in London, so I could deliver a petition to the British Prime Minister detailing our call for more Marine Protected Areas in the once abundant, but now drastically overfished, North Sea. To do this, we needed to swim up the River Thames – but the harbourmaster was having none of it. “Far too dangerous,” he told me.

Eventually we secured permission to end our swim at the Thames Barrier, which proved to be highly symbolic. When the Barrier was completed in 1984, its engineers thought it might be raised two or three times a year to protect London from flooding. But in the winter of 2013/2014 alone it was used 48 times. Without that barrier, London as we know it would literally drown.

The Thames Barrier is a rare example of foresight and visionary design. Ending our expedition here seemed fitting: we need more visionary thinking if we are to protect the seas that sustain us against the man-made threats of pollution, overfishing and climate change. Setting aside Marine Protected Areas is the most direct and straightforward way to do this.

It took me 6 hours and 22 minutes, over two days and three tides days to complete the final swim. As I stood next to the barrier, after seven swims in seven seas, many of them near conflict-ravaged regions, I didn’t think about what we’ll lose if we don’t take action now. I thought about how much we have to gain if we do. As Desmond Tutu reminded me as I set out on this expedition, conflict and environmental degradation go hand in hand. But the converse is also true: protecting the environment fosters conditions for peace.

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