Once we arrived in port at St Petersburg, we went on a water way tour of the main points of interest in the old part of the city. The Peter and Paul fortress that Peter the Great built to protect the city is remarkable.
The fortress has a wonderful website at this link.
In addition, the University of St Petersburg is among the top schools in the world and was the first university founded in Russia. It also is where Vladimir Putin was taught. The link to this school is here.
We did not go to The Hermitage museum as the crowds were overwhelming. However, if you've never thought about this unique museum before, here is a detailed look at the museum.
Waterway tour of St Petersburg