Sailors from far away have been visiting the Guadiana for thousands of years, the first to arrive were probably the Phoenicians from the eastern Mediterranean, who arrived about 1000 BC, not as conquerors but as merchants bringing with them dyes, fabrics, ceramics, glass, metals, wine, seeds for crops and olive oil to trade with the locals. They established a fishing port at Vila Real de Santo Antonio and ports at Alcoutim and Mértola further up the river.
To see a google map of this area click here.
Maps of the Guadiana made prior to 1858 show a ford between Alcoutim and Sanlúcar, the builders of this ford are not known, it could have been built by the Romans, the Visigoths or the Moors. It would have been built by filling barges with stone and sinking them in a long line across the river. With a maximum tidal range of around three meters it may have only been passable at low water on foot. In 1858 when ships began to collect copper ore from Pomorão it would have been too shallow for them to pass over safely even at high water, it is therefore assumed that it was removed to allow their safe passage. There is no record of this, but remains of the ford extending from Alcoutim about 30 metres across the river are clearly still there.
The photograph above I took in August 2008 when I stayed overnight with a Sunseeker Manhattan 50 on one of the two pontoons at Alcoutim. The cost of our overnight stay was 7.50 euros! The next morning we went on up to Pomarao (a total of about 30 kilometers up the river from the sea. We arrived at low water springs and as it was getting a bit shallow anchored about 500 meters before Pomarao. Had we arrived about two hours later it would have been deep enough to anchor off the village.
Almost 1000 years later the Algarve was conquered by Julius Caesar, then as the Roman Empire receded, early in the 6th century AD the Visigoths invaded from northern Europe and they too used the Guadiana for transport by boat and built fortified settlements on the banks of the river. For two hundred years the Visigoths ruled Portugal from their base at Toledo in Spain, towards the end of that period they split into two factions and one faction in the south of Spain and Portugal who had regular contact with Moorish traders from Morocco, who had established trading posts far inland as a result of using the Guadiana for transport, asked for help to defeat the other faction. In 711 a Moorish army crossed the Strait of Gibraltar, landing at Tarifa and within ten years had conquered most of Spain and Portugal.
For almost 600 years the Guadiana was in regular use by the moors for their transport and communication inland. By the end of the 13th century the Portuguese with a lot of help from Crusaders from northern Europe had defeated the moors and the Guadiana and its ports returned to Portuguese control.
By the 14th century with the Moors also defeated to the east of the Guadiana the river now became the border between Portugal and Castile. The Castilian kings attempted to get control of Portugal by both intermarriage and direct invasion. The Portuguese defended themselves by building impressive castles on the west bank of the river at Castro Marim and Alcoutim. The imposing castle built by the moors at Mertola overlooking the river was enlarged and improved at this time.
Much more recently, in the 18th century guard houses were built at regular intervals all the way up the river on the Portuguese side, the guards who lived in these houses had only one task and that was to keep a constant look out across the river in case of a Spanish attack. Many are derelict as the one in the photograph to the left, but some have been bought and either re-built or repaired.
In 1755 Vila Real St António was very badly damaged by the tsunami caused by the earthquake that damaged so much of the Algarve and Lisbon. It was not until 1774 that, thanks to the enthusiasm and drive of the Marqués de Pombal, the town was completely re-built a little further inland. He used the very latest concepts in town planning and created a beautiful town with a central square known as the Praça Marqués de Pombal which is ringed with lemon trees and attractive Portuguese symmetric 18th century architecture. Almost all of the buildings on the west side of the square are now cafés or restaurants with tables and chairs extending out into the square under modern sunshades making it a relaxing place to sit and enjoy a coffee, a drink or a meal.
Half way between Alcoutim and Mértola on the east bank of the river, where the Guadiana turns inland towards the northwest and so ceases to be the border between Spain and Portugal, is the very small village of Pomarão (shown in the photograph on the left and another to the right) which in 1858 became a busy port as a result of a British company starting a mine at São Domingos 15 km to the north. Mining of gold, silver and copper had taken place in this area since Roman times, and with the advent of more modern machinery, between 1885 and 1966, 25 million tons of copper ore were excavated from this area. The ore was transported by a railway line from the mine to Pomarão where it was loaded onto ships and taken approximately 45 kilometres down the river and out to sea to various destinations for processing. 
The Guadiana is no longer used by commercial river traffic but is still navigable all the way up to Pomarão and it is safe to anchor anywhere. Between Alcoutim and Pomarão it is very beautiful and remote as can be seen from the photographs above. There are pontoons off Alcoutim, Sanlúcar and Pomarão and off some smaller villages, some with electricity and water. I have sailed and motored up many rivers but for me the Guadiana beats them all. With its steep hills on either side, covered in the spring and summer with beautiful wild flowers; attractive cottages from a past era now mainly derelict but a few recently re-built in the traditional style. Small farms with orange groves, herds of goats tended by shepherds to keep them within the confines of their unfenced pastures and small fields which you will still occasionally see being ploughed by a man with a mule and a single furrow plough. The photograph on the left I took about 40 kilometers north of Pomarão near the town of Serpa.
3000 years since Phoenician sailors first visited the Guadiana it has now become a popular destination for sailors with yachts from a wide variety of countries. There is a new marina at Vila Real St Antonio called ‘Porto Desportivo do Guadiana’ (see photograph to the right) and whilst many visitors to the river may prefer to anchor and enjoy the solitude up river, the marina has a total of 360 very inexpensive berths, showers, ice for sale in the reception office, a slipway, bars and restaurants. There are supermarkets, a chandlery and various maintenance services close to the marina.
Try to arrive at either high or low water, the tide moves very quickly through the pontoons and maneuvering at any other time can be difficult.
To contact the marina by VHF call them on channel 9 or 12. By telephone 281 541571 or 281 513769. By email: anguadiana@mail.telepac.pt
There is also now a boatyard at Vila Real St Antonio, situated about halfway between the marina and the river mouth. I have written a seperate article about this boatyard, to see the article click here.
Martin Northey - Yachtmaster Instructor for Sail and Power
The Iberian Sea School - RYA Sailing, Motor Cruising and Powerboat School.
Apartado 1039 - Estaçâo de Correios de Vilamoura, 8126 - 907 Quarteira, Portugal.
Tel: 00 351 965 800702
Email: martin.northey@mail.telepac.pt
Web Site:www.theiberianseaschool.com
Skype: martinnorthey