By Lucy Ash

With a good wind behind you, it only takes 18 minutes to cross the Straits of Gibraltar on a sailboard. People come here to enjoy the surf and the beaches, and to admire the dolphins which come to these waters to breed. But I'd come here to investigate an uglier side to the landscape: this narrow stretch of water is rapidly becoming a graveyard.

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With Europe so close, perhaps it is not surprising that so many illegal immigrants from Morocco, other parts of Africa and beyond, are tempted to try their luck with a night ride on the rickety boats known as pateras. The risks are high: more than 3,000 have drowned on such crossings in the past five years.

The Straits are notorious for their vicious currents and they are congested with shipping - the skipper of a big ferry or ocean liner can easily run down a little boat without it even noticing it.

Eric Shaw, a marine biologist based in Gibraltar, spends every day in the straits monitoring the dolphin population. He has lost count of the number of bodies he has seen floating in the sea or washed up on the coast.

But there is another, less dangerous route for migrants. Ceuta and Melilla are the unlocked doors into Fortress Europe. These two small Spanish enclaves on the north coast of Morocco are the last fragments in Africa of a once-mighty empire ruled from Madrid. If the immigrants can somehow get in here - it is the same as being in mainland Europe.

There are long queues for food and water...

So many immigrants have arrived in Ceuta over the past few years that the Spanish government was forced to provide a temporary shelter for them at a former campsite. Most of the inmates are young men from Sub-Saharan Africa, but there are now people from 24 different countries at the camp including Algeria and Iraq.

At first there were just a few hundred, but now the camp houses more than 2,000 people. All need food and shelter and the site is hopelessly overcrowded. Every day, fights break out in the queues for water - and more people arrive every week. Even children have turned up here, some in their mothers' arms and others completely alone, carrying only name tags around their necks.

... but for many it's worth it for the chance of EU citizenship

But the potential rewards are great. Most of these migrants stay in Ceuta for two to five months. Then they are given temporary work and residents' permits and transferred to the mainland. After a year in Spain they can usually stay on legally. Many end up with Spanish citizenship and they then have the right to move anywhere within the European Union.

In fact the Spanish need the immigrants. The government has just agreed to issue one million temporary work permits over the next three years because although Spain has the highest unemployment rate in the EU, most Spaniards are not interested in low -paid jobs on building sites and fruit farms.

Captain Rebollo with a stretch of the newly-reinforced fence around Ceuta

Under some pressure from other EU members, the Spanish authorities say they are doing their best to stop illegal immigrants from getting into Ceuta. The eight and a half kilometre double security fence which separates the enclave from Morocco, is now being fitted with razor wire, infra red cameras and heat sensors. But if the migrants do manage to get in, it is virtually impossible to send them back.

"All those who come here have no identity papers whatsoever", explains Captain Jose Manuel Rebollo of the Spanish Civil Guard. "By some miracle the papers always get lost on the journey so we are dealing with people who have no country and no name. Where can we send them back to?"

Colonial insignia still decorate the pavements of Ceuta

Ceuta and Melilla have been European territories for 500 years and Madrid insists that they will forever remain so. But with a new king on the throne, Morocco is actively seeking the return of the enclaves and Spain may have to hand them over - sooner rather than later - if the flood of migrants cannot be stopped.

The situation in Ceuta today is made even more tense by the emergence of a new political party which arouses deep suspicion in Madrid. The enclave is now controlled by the Independent Liberal Group, known by the acronym GIL. It's no coincidence that Gil is also the name of its party leader, Jesus Gil - one of the most controversial men in Spain today.

Jesus Gil: too controversial to run a sensitive spot like Ceuta?

Senor Gil, a construction magnate, has been the mayor of Marbella since 1991. Some local people worship him and give him the credit for the renaissance of the resort. Others worry about his alleged misuse of public money, his contempt for planning regulations and rumours that he has close links with the Sicilian mafia.

Gil has long been at loggerheads with the Spanish establishment for years, and even served jail time for several offences. Now even the Moroccan Prime Minister, Abderrahman Yusufi, has stated the political infighting and controversy Gil has ignited in the enclaves "is proof that their current status simply cannot last."