Yes, we are talking about the corks that are normally found in a bottle of wine or sparkling wine. This is an industry which has been important for Girona province for 150 years. It is centred on the towns of Palafrugell and Cassa de la Selva, either side of the Gavarres hills where most of the cork oaks are found.
Cork is an amazing natural product which was discovered by the Greeks over 2,500 years ago to seal the amphoras of wine and olive oil they transported around the Mediterranean basin.
As well as being lightweight, it is waterproof and fireproof which means the cork oaks are some of the very few trees that survive the regular fires which sweep through most forests. The trees take about 30 years to mature sufficiently to produce a layer of cork (its bark) but another 15 is needed before it is thick enough to be used for commercial purposes.
So, this is no short term industry, the trees take about 14 years to re-grow its bark for the next harvest which is all done by hand up in the hills. This area is the second largest exporter of corks in the world after Portugal and some 1,500 people are still employed in some way by the industry locally.
Unfortunately, like all mature industries, there is severe competition from other methods of closing bottles which are more economic and the market for corks is sliding steadily. Their niche is still relatively secure in the more upmarket sectors of the wine and champagne sectors but the cheaper end is moving to plastic corks or screw-caps.
Make sure you come and take a tour of a cork making factory (ask at the local tourist information offices) or visit the cork museum in Palafrugell before this fascinating industry disappears forever!