Just to give you a flavour of the area here is a glimpse in a nutshell of some things you can do and see.
Ayamonte - take a walk around the old town, look at the yachts in the marina and dream, visit the morning market, have a coffee in one of the Plazas, climb to the viewpoint at sunset, try the wine, and be adventurous with the tapas. Try the same 'Portuguese style' by jumping on the ferry and crossing the River Guadiana to Vila Real de Santo Antonio (only a 10 minute crossing).
Seville - Take a drive to Seville (an hour or so from Ayamonte), one of Spain's most captivating cities and the capital of Andalucía, home of the Alcázar (Moorish palace rich in decorative tiles and carved ceilings) and La Giralda (98m high mosque minaret, now the bell tower of Seville's cathedral). Near the Cathedral, the Juderia's maze of white-walled alleys evokes the atmosphere of the Moorish city. Famous for tapas, flamenco, bullfighting, its horse fair and the Holy Week processions of hooded penitents.
Huelva - closest city to Ayamonte and the province's likeable capital. A big port with all the associated industries, good shopping and some great Spanish architecture.
La Rábida - Columbus set sail from here. On the outskirts of Huelva there is a visitor centre and replicas of his ships. Also well worth a guided tour around the monastery up the hill.
Sierra de Grazalema Natural Park - about three hours drive from Ayamonte and maybe an overnight stop (needs a holiday of its own really!) It's very mountainous, green and dotted with attractive white villages. Fine walking country and one of Andalucía's most beautiful areas.
Sierra de Aracena and Picos de Aroche - a smaller version of Grazalema, but much, much closer! A favourite spot with many marked tracks for both walking and mountain biking.
River Guadiana - the river forms the southern part of the border between Spain and Portugal, take a trip on it and/or visit the villages and countryside by it. Take a fast boat trip up the river, or out to sea from Punta del Moral. They have a high powered rigid inflatable boat that takes a maximum of 12 people for a 90 minute spin. There are also bigger boat cruises up river with a stopover for lunch if you prefer a more sedate pace.
Doñana National Park - under an hour away and a must. If you want to do a guided trip in the heart of the reserve in a big 4x4 you have to book well in advance. There are, however, many great places to visit in the 'pre park' that are perhaps just as good and you don't need a guide.
Mines at Rio Tinto - the largest open cast mine in Europe. A big hole with lots of Tonka toys and a train ride!
Silves - Restored red limestone walls of the castle dominate the Moorish capital of Al-Gharb ('The West'), surrounded by orange and lemon trees. Holds the annual beer festival!
Mértola - Roman/Moorish castle and old town overlooking the Guadiana river. A great place to lunch and visit the surrounding natural park and waterfall.
Tavira - Well worth a visit to this beautiful place. The town is situated on the mouth of the river Gilão and the two sides are linked by a Roman Bridge. It's full of great Portuguese architecture and alternative restaurants (20 mins from Ayamonte in the car).
Cacela Velha - small village with a great view of the Ria Formosa (lagoon system) and beaches. Take a short boat trip to the white sands.
Vila Real de Santo Antonio and Castro Marim - two towns you can see across the river from Ayamonte. Vila Real is a Portuguese version of Ayamonte, but with far more British tourists visiting from the neighboring resort of Monte Gordo. Castro Marim has two castles, one of which has been well restored and holds a very atmospheric medieval festival at the end of August. Monte Gordo In case anybody suggests it, avoid here. This is the exception that proves the rule. "Blackpool in the sun".
The reservoir at Odeleite - take a break from the beach and go swimming in fresh water! A couple of good local restaurants to be found.
Bird Watching - Everywhere.
Wild Flowers - Spring flowers are out as early as February and well worth visiting just to see them. It's a different place in the summer!
Mountain Biking and Walking - Spoilt for choice with all sorts of places to explore both for the experienced and not so. Bike hire is about €12 per day.
Fishing - A number of boats go from both Isla Christina and Vila Real. Some of the boats are even British owned and seem to be very popular.
Golf - Spoilt for choice.
Horse Riding - Several stables with lively horses for a ride through the pine woods.
Beaches - Endless!
Windsurfing, Sailing, Canoeing & Surfing - Kite surfing and windsurfing are very popular here. There is a sailing school which is open in the summer months and runs reasonably priced courses as well as renting out a variety of equipment including canoes. The surf is ok for amateurs but not for pros as the beaches are quite sheltered. The enthusiasts head east for the big surf of the southern Costa de la Luz.
Tennis - There is a friendly tennis club just outside Ayamonte. Courts are roughly €6 per hour.
Festivals, Fairs, and Markets - Loads everywhere.