It's not just a witty rhyme, it's a lot of fun! The '2 nations' in the title are Canada and the US. There are several ways to get to Canada from Maine...you have 2 opportunities to take the CAT ferry- from either Portland or Bar Harbor or, you can drive.
We did this about 12 years ago. We had just sold our old house and were feeling a bit footloose and fancy-free. We couldn't move into our new house for several months and we just weren't looking forward to moving into the 'interim housing' we had arranged so off we went.
We called ahead to schedule a berth on the old Scotia Prince and packed a suitcase and headed for Maine (we were living in Vermont at the time). After the 12 hour trip (it's a LOT faster on the CAT), we arrived in Yarmouth, Nova Scotia. With bagpipers playing, we disembarked and headed straight for the tourist info centre. We had NO idea what there was to see or do!
Inside, we found great help and decided we would follow the 'Lighthouse Trail' (we really like having a theme on vacation). With tour book in hand, we set off. We stayed at B&B's in several towns along the way, including Shelburne and Lunenburg.
Nova Scotia is obviously easy to get to via the CAT, but if you are driving, you can head to New Brunswick or Quebec City or Montreal.
Freeport is a great 'halfway' point if you are taking the CAT from Bar Harbor or are driving to NB, Montreal or Quebec City. If you are taking the CAT from Portland, White Cedar Inn is a great spot to stay the night before you board. Do a little shopping in Freeport and then head for Portland the next day! Stay here a few days after your return from Canada, too!
PS- Be sure to have ID for the border!