Aracena is the main town in the Sierra de Aracena Natural Park with a population of approximately 7,500.

Unpretentious but relaxed and pretty, it meanders up a hillside topped by the remains of its Moorish castle and a church built by the Knights Templar, the Church of Our Lady of Sorrows, which preserves the minaret of the mosque that preceded it.

A favourite holiday retreat of the Spanish royal family, Aracena is a busy, bustling little market town, relaxed and cheerful like so many in La Sierra de Aracena, an hour to the north-west of Sevilla and well on the way to Portugal. Welcomes are warm and friendly and you will feel immediately at home here.

Supping a cold beer outside one of the many little bars and taverns around the Plaza Alta in the centre of town, watching the world go by, is a very satisfying way to spend some time.

Here, old-fashioned, unpretentious rural Spain meets more trendy modernity in perfect harmony. Children on roller skates and scooters, giggly teenagers flirting and listening to music, old men earnestly debating the best way to grow a pumpkin, grandmothers fussing, women gossiping: all the generations in one space, a constant hubbub of activity.

It's a perfect size, a little country town, so not remotely intimidating, yet big enough to offer some excellent restaurants and tapas bars - there were 64 bars and three night clubs at the last count - and some good shops. The town also has a popular covered market, boasting three fish stalls and two meat stalls as well as plenty of fruit and vegetables.

Its Moorish castle and fine, thirteenth century church notwithstanding, the town's most famous landmark is the Gruta de las Maravillas, the "Cave of Wonders", the most visited site in the province of Huelva.

For centuries the townsfolk of Aracena were unaware of this marvel that lay, unsuspected, beneath the very ground they trod.

Discovered by accident (by a stray pig apparently … ) the Gruta de la Maravillas is the largest cave in Spain, a mile and a half long, and is truly a marvel of subterranean lakes, striking colours, cathedral-like chambers and all manner of exquisitely adorned stalagmites and stalactites.

As the brochure says "Water has written a poem through the silence and slowness of the centuries".

The cave served as the backdrop for the film "Journey to the Centre of the Earth" and the names of the individual chambers sound like they were dreamt up by a Hollywood scriptwriter. But they are, in fact, an accurate reflection of the rock formations found inside - the Cathedral, the Sultana's Bath Chamber, the Emerald Room, Godʼs Crystal Room, the Submerged City, the Enchanted Tannery, the Chickpea Room and the Gallery of Nudes.

At the entrance to the caves there is a helpful tourist office and a small geological museum with minerals from all over the world.