We are assured that our tour on the second day will be back to the ship in plenty of time. We have booked with a long-standing tour company (Insider Tours) who do this hundreds of times every summer and have an excellent reputation so I'm confident we'll have no problems. If you would like to check out this wonderful tour, go onto the Insider Tours website and look for "St. Petersburg Delights 2-day Tour", which is what we are taking. We'd love to meet you on that!