I was told you can take a bus near Wangfujin to go to the Great Wall that costs only 10 RMB. Is that right? If so, do you know exactly where that bus station is?

Also, I went to the Badaling Great Wall twice and the first time a cable car took us to the top, but the next time the tour guide left us at a different entrance where there was no cable car but some sort of "roller coaster car". Do you know the names of these two entrances?

Thanks