Our trip would be about 95 miles (of road travel) from the Boston area to Martha’s Vineyard, just outside the likely comfortable range of a highway driven Leaf. Another factor to consider was that the family would be along, so taking too many risks with range was out of the question. In addition I had to count on using climate control should it become necessary. (There’s a whole other post waiting to be written about being a hyper-miler in a family of normal people.)
The Carwings online system is a great place to start planning, offering the ability to plan your trip, including routes, distances and the possible need to charge along the way. It also takes into account things like terrain, and incorporates data acquired from other owners making the same trip. Some trips of course don't have prior data, but often there is some good information.
There are also apps that show public charging station locations but it’s worth noting that not all sites or apps have the same information and not all of the information is current. So it’s always worth confirming data from a number of different locations.
Anyway, because the trip was a little too long, I looked for opportunities to charge along our usual route and there was a cluster of charging options near Bridgewater, MA (about 35 miles into the trip.) After that, the next opportunity would be on Cape Cod itself, just over the bridge at a Nissan dealer. The stations near Bridgewater were at a 99's Restaurant or a Chili's and we chose the Chili's because it is within walking distance of a Lowes (since we needed to entertain kids while charging for around an hour. That’s why waiting until the Nissan dealer was out…just not much to do at a car dealership if you’re a kid.
I also liked that we had several charging options in that same location, because you can't guarantee that the chargers will be available when you get there. Another route offered a few charging stations at a mall, but was many miles out of the way.
So that was the calculus for the decision we made to stop where we did. I did the math and knew how much charging we would need to make it to our destination with a good comfort zone. Hearing from some experienced Leaf drivers, I learned that the car takes longer to fill at the top end of the battery than the bottom. As you near full, things slow down a bit. This was unfortunate in our case because we were forced to charge early in our trip, meaning an inefficient use of our charging time. But it was what it was.