On this tour, we took a 30-35 min bus ride outside the city to the Madrid wine region. We visited three wineries and learned more about Spanish winemaking, including a visit to a wine cave to see historical clay pots that were once used in the winemaking process. The tour was very informative, and overall, the wines we tried were very good, especially given the price. Wine bottles at the wineries we visited ranged from 5-20 euros each, which is a steal given that you can easily spend $50+ for a bottle at California vineyards.
In addition to wine tastings at each winery, there were some snacks (be prepared for lots of ham and cheese!) as well as clean restroom facilities. Our group was around 12-15 people, all hailing from the US, so depending on where you're from, it can be a nice experience to spend some time with fellow Americans and compare notes on attractions to visit while in Madrid.