As of August 2018, there are many minibuses departing Kraków bus station around every 10 minutes to get to Kalwaria Zebrzydowska in 45 minutes. The bus station in Kalwaria Zebrzydowska is around a 15 minute walk up a fairly steep hill to the basilica. I found it to be lively but not overly busy. I particularly enjoyed the walk around the other small chapels. From the basilica, it is mostly downhill apart from a couple of steep sections near to the basilica. There are two possible trails, but they follow an almost identical route and with a reasonable map (I highly recommend the offline mapping app maps.me) it is possible to visit all of the monuments without much backtracking at all. The trails are, for the most part, wide grassy paths or unmade roads. The whole visit took me just over 2 hours.