San Marino questions

You can begin exploring transportation options on Rome2Rio.com. It's important to understand that the specific information displayed for fares, travel times and frequencies is often laughably wrong. The website is usually accurate about the existence of the various transportation options and where you might need to transfer. There can be day-to-day variation in availability, though. If you keep clicking through the website you'll eventually find the name of the bus company providing the service on each leg of the trip. There will probably be a link to the bus company's website where you can find accurate information on schedules (and maybe also on fares).

I'd encourage you to consider all the options you'd have for your extra days post-tour and ask yourself how San Marino stacks up to them. Nothing I've read about San Marino has sounded positive enough to justify the amount of travel time you're talking about. It's not as if you'll be driving practically right past it on the way between two other stops. Your tour spends only 2 nights in Rome and 2 nights in Florence. Both cities deserve more time, especially Rome. The tour doesn't seem to include Siena, which is easily accessed from Florence. It doesn't go to Venice, which is farther away but can be reached in 2-1/4 hours on a Freccia train. If you prefer a less-busy destination, Ravenna, home to some of the world's very best Byzantine mosaics, would be easier and faster via public transportation than San Marino. There's a reason why so many people go to all those places and few bother with San Marino.

You can stay in Bologna after your tours ended and take day trips to San Marino, Ravenna, or join a food tour.

It takes about two and a half hours from Bologna to San Marino. The transportation is easy. First take the train to Rimini, buy the bus ticket at a store across from the train station and the bus station is about fifty feet from the store.

I have to admit that there is not much to see in San Marino. I have done all my sight seeings in a few hours plus a leisure lunch. The reason I visit there is because it is in my bucket list since fourth grade after I read about it is one of the smallest country in Europe. The article did not even come with a photo but a fuzzy drawing of a funicular going down hill but some how I am hooked. Honestly speaking, I can hardly find a reason to visit there a second time.

While consensus appears here that it's not worth it, I would disagree. We were there in 2017 on our honeymoon and visited just for a few hours en route from Ravenna south. Albeit we had a car so it was not a complicated stop, and I don't remember any particularly windy or difficult roads. There is one truly wonderful site that for me was worth the effort. Monte Titano is about 2500 feet above sea level, but walkable on a paved path. It is topped with the Fortress of Guaita, built in the 11th century. Guaita was once a prison but now contains a small museum filled with military memorabilia of centuries past. The draw here is view. I don't remember using a guidebook, but Fodor's may have had something. A little online research will do the trick. Private message me and I'll send you a few photos, or just take a look at the Trip Advisor and Wikipedia entries for San Marino.