Explore Vienna's medieval past by embarking on a quest on a mobile phone app. Uncover Vienna's history in a unique way by solving riddles and following clues to complete your challenge. Download the free Questo app on to your mobile phone and begin your self-guided tour at the starting point. Then, head off to discover Vienna's taverns and narrow medieval streets. Unearth traces of the greatest tragedy in Vienna's history, the plague, as you are guided by the bizarre story of the city's most famous balladeer, Marx Augustin. Learn more about the man locals call Lieber Augustin (Dear Augustin) because of his charming humor in bitter times. Unlock secret stories of the places you visit every time you solve a clue or riddle. Upon the successful solution of a clue, you will receive exact directions to the next location, removing the need for a map, GPS, or guide for your city exploration adventure. For larger groups, one person can purchase access for the entire group by selecting the number of people in the group. All group members will be able to play the city game on their smartphone. Alternatively, each person can purchase their own ticket. You can play as a group and solve the clues together as you walk, or you can split into smaller groups/teams and compete against the others. Each person can also play on their own, separate from the group, and meet the group at the end.