Hi Nick and welcome to Cruise-Chat.
You're going to love the Summit and the Med. What a great choice for a first cruise! I assume you know that one of the few drawbacks is that you'll get addicted to cruising?
Well most of us don't consider that a drawback...
There have been a lot of discussions about what to see and do, and who can help you. You may want to check in our Port Chat section, and particularly our Europe Port Chat
section, and take a look at the past discussions. You can also search that section using a keyword or two.
I've heard about ShoreTrips, which seems to have a good reputation, but I've never tried them so I'm not endorsing them in any way. Others who have tried that company, as well as other companies, surely will chime in.