YOU HAVE PLUNGED INTO WATERS where undersea life flourishes and history lurks. Nearby, waves crash against an ageing stone fortress which guards a Mediterranean harbour that has existed since the days of Egypts pharaohs. Its the last sound you hear as you descend.
 Below rests an ancient world drowned by catastrophe. Fish flutter around giant stone blocks and strange shapes that litter the seabed. Ahead, a dark form beckons from its watery tomb. You swim closer.
 A black face emerges from the cloudy waters, its pitted eyes gazing through your mask. A feline body anchors this stoic visage to the bottom of the sea, where this sphinx has rested undisturbed for hundreds of years.
 Youre face to face with the past in a world where currents flow with memories of Alexander the Great, Cleopatra, Julius Caesar and Mark Antony. This is the stuff of divers dreams.
 Such underwater experiences have become reality as Egypts seaside city of Alexandria witnesses the beginnings of a recreational diving industry, along with ambitious plans to exploit its submerged history for tourism.
 Now the greatest obstacle to safe aquatic activities - pollution - is being tackled in a bid to ensure success.
 Even without its wealth of submerged treasures, Alexandria offers plenty to fuel the imagination. This city of 4.5 million has a European charm, its public squares protected by heroic statues, sidewalk cafes, patisseries and hundreds of shop-signs competing for attention in French, English and Arabic. Colonial-style buildings weathered by the salty air face the Mediterranean, overlooking crowded beaches and a bustling promenade that hugs the crescent-shaped Eastern Harbour.
 A stone citadel stands guard on the rocky jetty. Its been a landmark since Mamluk ruler Qait Bey erected it 530 years ago, on what some say are the foundations of an ancient wonder.
 But Alexandrias greatest treasures lie 6-8m beneath the waves. Out there are the awe-inspiring ruins of the Pharos of Alexandria - the lighthouse known as the Seventh Wonder of the World - Cleopatras palace, colossal columns and drowned stone gods.

Australian Paul Garwood was among the first to sign up when the citys first recreational dive operation, Alexandria Diving Co, opened last May. He found it fascinating but radically different from his previous dive experiences in the Red Sea.
 The two offer very different things for divers, he says. Its coral reefs, clear water and thousands of fish versus rubble and stone slabs, murky water and poor visibility. But the Eastern Harbour dives were special because of the history involved. Seeing a 2m-long sphinx or blocks that people say might have belonged to an ancient Alexandria lighthouse was special.
 Garwood came across two sphinxes, broken columns, a hieroglyph-covered obelisk section and scores of granite blocks and massive slabs. He was diving on a site inaccurately dubbed Pharos City, just offshore from Qait Bey fortress.
 The diving was a challenge. The visibility was poor, about 2m, he said. It was like swimming through murk until you got to the object you were supposed to see. The first thing I saw was the seafloor covered by giant shapes, but I couldnt distinguish anything.
 You dont see a sunken city with streets and other remains. I was among all the murky water and broken pieces of granite, looking to recognise something historically significant. Eventually I came across the sphinx.
 Seven years before Garwoods personal discovery, French underwater archaeologist Jean-Yves Empereur first saw this magical site.
 The images of a drowned past haunt Empereur, who now heads the Centre dEtudes Alexandrines.
 When you see small fish playing with the sphinxes, it gives a more powerful impression of these sacred monsters of Egypt, he says. When you see ruins under water its even more impressive than on land.

The greatest impression made on Empereur was in 1996, when he stumbled across a regal red granite head of Ptolemy II, gazing into the sand.
 You are in front of a big moment of history when you come face to face with the person who opened the lighthouse and the Library of Alexandria, he said. Its immediately impressive.
 Stirring finds have also been discovered in Aboukir Bay, 14 miles east of Alexandria. Artefacts from the legendary cities of Canopus and Menouthis have been recovered and, in 2000, a team led by another French underwater archaeologist, Franck Goddio, pinpointed a pharaonic city, entombed in sediment four miles offshore.
 The city is Heraklion-Thonis, a port that guarded an ancient branch of the Nile before the river shifted and, for reasons unknown, the land slipped beneath the sea.
 Aboukir also provided the watery grave for Napoleons fleet, sent to the bottom of the bay by Nelson during the Battle of the Nile in 1798. The remains were excavated by Goddio and his team in 1999.

That divers and underwater archaeologists have been fishing artefacts from Egypts coastal waters for years is no surprise. The history of this region flows back thousands of years, when Pharos Island harboured ships laden with goods from Crete, Phoenicia and the Aegean islands.
 Greek historian Herodotus wrote of great cities along the Nile Delta when he visited Egypt in 450BC, more than a century before Alexander the Great swept through the area and founded Alexandria.
 Alexandria prospered as the Mediterraneans most glorious city under the Ptolemies, the dynastic Greek family that reigned as pharaohs over Egypt. The thriving port once boasted the Pharos and the Library of Alexandria, the worlds greatest storehouse of ancient knowledge.
 Alexandrias grandeur declined in the 4th century AD under Roman rule until earthquakes and tidal waves dealt a final blow to the city and its surroundings, burying their glory until modern explorers started dredging up the past.

Egypts sunken secrets only started coming to light in the past century, but it took an amateur Egyptian diver to stir up interest in Alexandrias offshore treasures.
 Alexandrian Kamel Abul-Saadat has had little credit for his remarkable achievements, but he identified two submerged sites around the Eastern Harbour back in 1961. To the east, he discovered a staircase surrounded by white marble columns, a life-sized Roman statue of red granite, a gold coin, a cylindrical chair and sarcophagi.
 Around Qait Bey fortress, he found two headless sphinxes, marble columns and a massive statue split in two. A year later naval divers raised the 25 tonne colossus, a 3rd century BC granite statue of Isis.
 Abul-Saadats stunning discoveries sparked a UNESCO survey mission in 1968, which confirmed his finds. His work also spread to Aboukir Bay where, by 1969, he claimed to have identified four of Napoleons sunken ships, including the flagship LOrient.
 Fifteen years later, Abul-Saadat died of a heart attack there while helping a French team explore the wooden hulls.
 Shifting sediment and pollution buried Abul-Saadats finds under a thick blanket of muck, but his legacy of rudimentary drawings, scrawled notes and tales of sunken wrecks inspired the next wave of undersea adventurers.

Todays explorers are armed with the latest technology, such as sidescan sonar, magnetometers, sub-bottom profiling and GPS, to help them penetrate the choking sediment and peer into the past.
 This hi-tech era began in 1992 when Franck Goddio and his Paris-based European Institute for Underwater Archaeology began electronically mapping the Eastern Harbour. The work was the backbone of later missions, including an underwater survey in 1996.
 Subsequent excavations revealed scattered remains of Alexandrias Royal Quarter, submerged more than 1600 years ago by earthquakes and floods.
 Goddio looks back fondly at his discoveries in the Eastern Harbour, which included Antirhodos Islan, where Cleopatras Palace once stood; a royal pier with a shipwreck; a sunken peninsula where the queens Roman lover Mark Antony built his personal retreat; a shipyard; statues and scores of outstanding artefacts.
 Its so emotional to see something that nobody has seen for 2000 years, says Goddio. Its beautiful, its superb.
 Now such emotions can in theory be experienced by any qualified diver. The sunken Royal Quarter has become one of the main dive sites for a local company that promises to expose recreational divers to Cleopatras wonders.

Meanwhile, offshore from Qait Bey, Empereur is piecing together scattered remains of what he believes is the Pharos lighthouse, which rose 100m until levelled more than six centuries ago by an earthquake. This too is a site earmarked for leisure divers. Yet its discovery seven years ago was a fluke.
 Work on a breakwater had exposed some sunken ruins and artefacts near the fortress. Empereur and a Franco-Egyptian team were called in to investigate and discovered a seafloor littered with artefacts.
 The French researcher and the Centre d'Etudes Alexandrines have since mapped a 2.5 hectare area scattered with 2500 pieces: columns, sphinxes, Greek statues, immense granite blocks and obelisks inscribed with names of pharaohs.
 Empereurs latest finds are the legs of colossal statues of the Ptolemies, which he plans to scrutinise in greater detail this autumn.
 The team has also excavated four of about 40 Greek and Roman hulls discovered just north of Qait Bey in 1996.
 The vessels, from the 4th century BC to 7th century AD, came from all over the Mediterranean - Crete, Palestine, Rhodes, Asia Minor, Tripolitania and Italy - revealing Alexandrias importance for trade in the ancient world.
 Today, you can visit these ancient shipwrecks, as well as the more modern wrecks of sunken cargo ships, via a short boat trip from the Eastern Harbour.
 These discoveries have also sparked calls for a marine park, to include the worlds first underwater museum. Such ambitious plans have the endorsement of the Egyptian government, underwater archaeologists and UNESCO, which wants Alexandrias offshore area designated a World Heritage Site.
 Eight projects have been pitched for the Eastern Harbour, including undersea Plexiglas tunnels, diving platforms, glass-bottomed boats and tourist submarines.

The struggle to undo the environmental damage from four decades of extensive water pollution around Alexandria, however, has kept such plans from surfacing.
 About a third of the million cubic metres of daily waste from Alexandria is dumped untreated into the waters off the citys crowded beaches. The worst offender is an outfall near the submerged ruins of the Pharos, which spews 200,000cu m of waste per day.
 West of Alexandria, a pumping station dumps in the sea 7 million cubic metres of agricultural drainage water, saturated with fertilisers and pesticides. All this, astonishingly, is an improvement over 1996, when as many as seven outlets poured sewage into the sea.
 It was only last year that the authorities closed the last remaining pipe that flushed waste into the relic-rich Eastern Harbour.
 The legacy of this pollution is a constant blanket of crud that covers many of the finds within the harbour. Underwater archaeologists often fight a losing battle to clear the sediment long enough to excavate their discoveries. And the visibility usually goes from bad to worse.
 Hassan Awad of the University of Alexandrias oceanography department was one of the first to suggest an underwater museum/marine park. He insists that nothing should be done until the waters are clean.
 We cannot open the area for tourists... it is not safe to open without providing healthy conditions, he says, adding that a single tourist catching typhoid or another disease would sink the whole idea. We cant start anything in the area before 2003.
 That is when the first phase of Alexandrias new wastewater treatment plant is due to be finished, diverting sewage and industrial waste to Lake Marouit, a coastal lagoon south of the city.
 However, Lake Marouit empties into a bay west of Alexandria, giving pollutants an escape route into the sea, and possibly back to the harbours and beaches.
 So Egypt is planning to build a second wastewater treatment plant at Lake Marouit by 2010. Only then do scientists say the water will be truly safe.

Despite the environmental drawbacks, the Egyptian-owned and operated Alexandra Diving Co has already taken the plunge, offering divers package tours and boat dives in these dubious waters for US $45 a day plus rentals.
 The PADI-certified diving centre, located on the beach of the Eastern Harbour, is run by those who worked with the Egyptian underwater archaeology department during the discovery of the Royal Quarter.
 Most of the Eastern Harbours submerged ruins remain out of reach to visitors but the upstart company does offer a dive to the Royal Quarter, with the chance of exploring the wreck of a World War Two aircraft which rests on top of an ancient street and an ancient Egyptian boat wreck - all at 6-9m.

Other shallow dives take place outside the harbour near Qait Bey, exploring the scattered blocks, broken columns, statues and mysterious remains that have kept Empereur busy for the past seven years. It was here that Paul Garwood had his brush with the past.
 Despite the poor viz, Garwood says the pre-dive briefing from a knowledgeable dive master and an expert from Egypts Supreme Council of Antiquities made the dive a success. I wouldnt have gotten a lot out of it if I hadnt been told about what Id see, he says. The preparation made all the difference.
 But it isnt for everyone. There are many dive sites in Alexandria with archaeological interest, but youd have to be a real archaeology buff to want to continue to dive there, says Garwood.

As underwater archaeologists continue to explore Egypts coastline, the promise of more dive sites to explore is always there. Ibrahim Darwish, director of the underwater archaeology department with the Supreme Council of Antiquities, underscores Egypts offshore potential.
 Along the north coast of Alexandria to Sollum [125 miles west] there are more than 35 cities under water that havent been discovered,he says, referring to references in classical texts.
 We need 100 years to discover all that we have.

the
the ancient sunken quarters show up yellow on this map of modern Alexandria and its harbour area
underwater
underwater archaeologist Franck Goddio has charted and excavated the Eastern Harbour
fishermen
fishermen at the dive site at Qait Bey fortress, where thousands of blocks have been discovered under water
Jean-Yves
Jean-Yves Empereur of the Centre for Alexandrian Studies
Franck
Franck Goddio with an intact stele covered with hieroglyphs at Heraklion
the
the Eastern Harbour
Qait
Qait Bey fortress guards the entrance to the Eastern Harbour
diver
diver using specially developed underwater differential GPS to pinpoint a sphinx
marble
marble head of the god Serapis in the sunken suburbs of Canopus
Alexandria
Alexandrias modern promenade

FACTFILE

GETTING THERE BA and Lufthansa offer direct and indirect flights to Alexandria from UK airports. Major airlines also offer direct flights to Cairo, where you can either take a two-hour express train 140 miles north to Alexandria, bus or taxi.
DIVING: Alexandra Dive Co is Alexandrias only dive operator. It has two dive boats and offers full equipment rental (about£21 a day). Individual dives start at around£36 (two-dive/day minimum). 0020 3480 0363, www.alexandra-dive.com
ACCOMODATION:Hotels are plentiful, though availability is limited June-August. In descending star order try the Helnan Palestine, 020 3547 3378; Sofitel Cecil, 0020 3483 7173; Metropole, 0020 3482 1457; or Semiramis, 0020 34830824.
COSTS: Regal Holidays is offering packages on selected dates from May, including flights, transfers, five nights at the Sofitel Cecil or Windsor hotels and up to nine dives for£899.
BEST TIME TO GO:Weather good all year round. High season June-August, when Cairo residents head to Alexandria.
FURTHER INFORMATION:Egyptian Ministry of Tourism, www. touregypt.net; Supreme Council of Antiquities, www. guardians. net; Franck Goddio, www.underwaterdiscovery.org