Our tour guide Katrina was fantastic. She was both energetic and knowledgeable of both history and culture. For 3.5 hours, she kept me and my wife entertained - stopping at all of the different historically significant locations (palaces, cathedrals, museums, etc.) and then explaining the background, history and significant. I had debated other tour companies, but am glad we chose this one. Even though it is more expensive, the small group nature (it was only my wife and I) that made it unique and enjoyable, because we could hear what she was saying, we proceeded at our pace and we could ask questions. We saw other tour groups on our walk (20 - 30 people) and could not imagine being in such a large group. Since we were only in Vienna for two days, this was a great way and efficient way to kick-start our first day as my wife and I felt that we really had a strong understanding of the history and familiarized ourselves with directions in the city after this tour. Katrina left us with suggestions for things to do on our own during our second day, which we did (Schonbrunn Palace, Belvedere, etc.) and they were great suggestions. If you are considering booking this tour and company, we would recommend you do it - you will not regret it!