Barcelona tube

Earlier this year, I mentioned going on a trip to Barelona.
Well. I went, I saw and I enjoyed it.
One of the things I enjoyed most, was the metro system. It is very practical : you enter a station somewhere in the city, take a train, maybe switch lines halfway and leave a metrostation in a totally different part of the city in no time.
I noticed that the metro trains in Barcelona are airconditioned, but the stations are not. Once you're on a train the temperature is enjoyable, but in the stations it can be realy hot. It is sometimes even hotter in the stations than it is above ground.
Prices are acceptable. You pay 1,25 EUR for one ride, but when you buy a pass for 10 rides (6,90 EUR) or a one (5,25 EUR) or two-day pass (8,30EUR) , it costs even less.
You can use the same ticket on bus and tram in the Barcelona area.