My wife & I signed up for this tour months in advance of our recent trip to Frankfurt. We received confirmation via email. We arrived at the arranged pick-up site only to be told by the guide for another trip (to Heidelberg), that, because we were the only ones who signed up, our tour had been cancelled! (There was no notification of any kind to confirm this). The guide told us that our only option was the Heidelberg trip, but that “it was better than spending the day in our hotel”!
I appreciate that the tour company did refund the difference in cost between the tours, but canceling the original tour with no notice is no way to treat customers!