Yes fully agree with what Matthews said and funnily enough we did exactly the same. The highlights in the morning gave one a really good feel of all the major sights in the city itself and the evening trip to the Hermitage was fabulous as that way one avoided the crowds which can be massive and spoil the spectacle. Although expensive it was definitely the highlight of the whole cruise and something I will never forget - we literally had the Hermitage to ourselves and it was just unbelievable. The problem with St Petersburg is there is just so much to see and thus one has to accept that one has to prioritise - in our case we missed out on the palaces which are about 30 minutes outside the city and are suppossed to be fabulous - they are for next time!!
Some people go on 12 hours a day tours for two days but that would be no fun for us but is an alternative if you want to really pack in a lot. To do that it is probably best to book in advance with a local tourist company but if you want to be more selective book with the ships tours. You have to do one of these as otherwise you would need a visa and this is not adviseable as the ship docks about 10 miles outside the city and you would need to speak Russian to have any chance of doing it yourself. Have a great time because St petersburg is a really exciting destination.
Thankyou very ..grateful.
Yes, we did the highlights tour in the morning, and the evening trip to the Hermitage, which included a guided tour followed by a concert. Can thoroughly recommend it, even if you're not particularly a classical music fan.