Despite all the negative Yelp reviews, I actually enjoyed this tour. I have never seen a real live…read moresea grotto before and to be underground in a miners cave and a lake was pretty cool. Europe's largest underground sea grotto! It was an old mining cave in 1913 then it got flooded which became the grotto. We did a walking tour through the tunnels and then a boat ride. Our tour guide spoke German and then used an audio player to play the English translation. There was no light for 20 years and they used blind horses to lead and carry equipment. The lake doesn't seem to be that deep from the boat. No signs of animal life. The movie Three Musketeers was filmed here with a 20 minute cave scene. Highly recommend. It can be a bit chilly in the cave and be aware that there are areas with steps. After the tour, you're allowed to wander around as you head towards the exit.

Don't do it. First off, it took us forever to figure out the trains to get here. Once we arrived we…read morewere excited for the tour. However the entire thing was in German. At the very end our tour guide said two sentences in clear English. Meaning he totally could have at least said a summary sentence for us the whole time. I realize that English is not the native language here but it's a tourist trap w tons of English speakers. Even the boat ride was short and uneventful. Boring and not worth it at all. Tour guide was also super rude to us!

This is an amazing castle in a beautiful wooded area. It's an easy day trip from Vienna, you can…read moretake the U6 to Siebenhirten and then the 270 bus and then a steep walk up the hill. The tour is 8 euro and runs on the hour in English and German. You can't take a stroller into the castle itself.

A castle the looks awesome from the outside! Worth the trip from Vienna just to see it. We were too…read morelate for the tour but will go back and check out the inside. Will update when we do...