One of the ship's excursion staff, David, was very helpful to us in choosing what to do in the ports. On his recommendation, we took the ship's shuttle into town, which dropped us at a main square (now mostly under construction),then took a canal boat sightseeing trip. We ate lunch and sampled local beer at one of many cafes along the canal (very expensive!), then walked through the market and apparently higher-end shopping areas to the King's Gardens. I was still jet-lagged, which limited my interest in any more sightseeing, so we had coffee at another cafe and then went back to the port.
It was a lovely day, but I felt we didn't make the best use of our time. Perhaps planning ahead more would have helped. Our fellow cruisers who took the HOHO bus (which picked up right at the ship) said it was worthwhile. Added bonus: In the middle of the night after leaving port, we passed under the bridge between Copenhagen and Sweden. On the way back to Harwich, we passed under it again about 11 pm. Many of us were out on deck in the front of the ship to experience going under the bridge. It looks so low--and the ship seems so tall--that you think you're not going to make it. Very fun!
On the first day, we went to a few photo-op spots in the city, then drove to the Peterhof Gardens, where Luba toured us around and steered us to a lunch tent for blinis. Afterward we went to the Tsar's Village and toured Catherine's Palace. It may not sound like a lot of sightseeing, but it was nearly 100 degrees F, very humid, and the driving took up a fair amount of the day. We were exhausted so we didn't join in the separate-cost "fun" tour with SPB that evening. Our fellow travelers, all of whom are CC members, I think, said that part--a canal ride with vodka tasting, and walking along the river--was enjoyable and faster-paced. The morning of the second day featured a trip to the St Peter and Paul Cathedral inside the fort, as well as a visit to the Church on Spilled Blood. Then we had pierogis for lunch, followed by a short shopping stop and a tour of the Hermitage, which lasted about 90 minutes. We were back at the port by about 4 pm.
I'd been to SPB about 40 years ago, on a student tour while Russia was under Communist rule. Most of what we saw on this tour had not even been open to the public during my last visit. Only the Hermitage was a place I'd been before, so it was like seeing two completely different cities. St Petersburg was by far the most exotic port we visited on the cruise, and it was good to have two full days there--even though what we visited barely scratched the surface of things to see and do. I highly recommend SPB Tours. Viktoria, the owner, was easy to deal with, honest and followed through on everything. Luba was terrific as a tour guide, as well.
While some of our fellow cruisers walked from the port to the old town, it seemed to be a fair distance just to get out of the port area. To maximize our time, we took the less expensive HOHO bus from the pier once around its route, which included the modern city, then got off at the upper part of the old town and started seeing the medieval sights. (There were two HOHO tour companies, but the other had three different lines and looked too time-consuming. The bus we took cost the same as taking the port shuttle both ways, but provided narration about the sights as well.)
There were plenty of churches open to the public, and one had a ceremony in progress complete with singing, which Estonians are apparently famous for. We took about a zillion photos of the winding streets and picturesque views, stopping here and there to shop or sit for a few moments. We ended up at a cafe on the main square, where we took a break over a beer and snacks before heading back to the port--where we did some more shopping at the stalls.
While we saw quite a bit of the city in one day, I'd love to go back so we could visit the museums. And shop, of course. The only possible downside was that the town was overrun with cruise ship visitors. Not only the Jewel but two other ships were in port that day. It made for a lot of crowds everywhere we went.