Yes on site there is a booth.
Buy on site
You can buy on it on site. Its $30 for individual which I recommend and $45 or $50 for a guided tour. You get 5 wine tastings . Enjoy Its an amazing place.
Easiest to do is on sight, you ask about avail next tour, pay, and off you drink ;-)
You can purchase by calling the phone number for the castello, and i believe you can purchase tickets at the location, though im not 100% positive.
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