Travel to krakow

I would recommend the “free” walking tour of Krakow by Walkative. It ends at Wawel Castle. In my opinion, the outside of Wawel Castle and the Church are what to see there. The interior of the castle was a let down for me. Better sights to see with only three day.
I used public transit / DIY for Auschwitz so I’m no help there. I would highly recommend visiting Wieliczka Salt Mines. You can DIY or book a tour there too. Krakow is wonderful.

I also used two Walkative tours in Krakow and thought they were good. The Castle itself was fine but I wouldn’t go again. However I did really like the chapel with an audioguide. And the grounds (free) are pretty.

There are advantages and disadvantages to using Viator or Get Your Guide. I haven’t had a bad experience yet, but some have - since both are third party companies. But sometimes I try to book direct and the same tours are either not on the company website - or the company doesn’t HAVE a website. So it’s hard to make a blanket statement. And sometimes the cancellation policy on Viator and GYG is better than direct (that makes no sense to me, but there you go).

There is so much to see in and near Krakow it’s hard to say where to start. We didn’t use Walkative in Krakow so I can’t comment there, but have used them in other cities with success (today in Wroclaw for example). I used Mr. Shuttle to go to Auschwitz, which was the path of least resistance. For me, organizing transportation and buying tickets in advance was too much work. A tour makes everything easier and saves time. I had a 7 am pickup and was home by about 1 pm, so I still had half a day available. The salt mine is fun, and buying tickets in advance and taking the train was easy. Much better bargain than paying for a package tour. You might want to look check the posts on Wawel Castle with teens before deciding on that one. If you want to go to Schindler’s factory, start looking for tickets now. I don’t know how far ahead they go on sale, but I tried to buy them eight weeks before our trip and they were sold out. We ended up having to go with Discover Krakow (oops, edited, originally got the company wrong), which was fine except it costs more and you have to stay with the group instead of taking things at your own pace. We used two Tours by Locals guides in Krakow and both were terrific.

Getting to Auschwitz is the subject of many discussions here on the forum - here is a current one:

https://community.ricksteves.com/travel-forum/day-tours/reputable-tour-company-from-krakow-to-auschwitz-for-auschwitz-tour

You can use the Search function for the website to find additional posts regarding Auschwitz - access the Search form by exposing the site menu - the icon with the five horizontal bars at the upper left. You can also just scroll down the list of posts for Poland - it's a frequent topic.