We went on the tour which we thought was extremely good value for the price paid. The guide was knowledgable and helpful. It is definitely worth paying the 5 euros as although you can wander around on your own, you would not get the same insight. Obviously it is geared to enticing you to buy the stuff at the end, but there is no hard sell its just left up to you. Tour lasts about 30 minutes with seemingly unlimited tastings at the end some of which were free, the more expensive ones had to be paid for by the glass. All in all a very interesting and enjoyable afternoon
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