Book two tours from Viator.com, on a Bucharest Romania based tour called "Private Tour of the Black Sea Coast: A journey from Romania to Bulgaria". I booked twice on this multi-day tour only to have each booking canceled, the first canceled with little time, and the second one canceled very last minute, less than a day or so from planned start. Both tours were canceled, even though they showed availability on the site and the site took the bookings and credit card payments for each reservation. Because the cancellations were so last minute, made it very challenging to change to an available alternative tour as others were already booked. If you are going on a distance journey to get to the starting location, only to have planned tours canceled, really ruins a vacation. Don't count on Viator tour bookings. A third tour also shown on site showed times a castle was opened that was incorrect.