I improvised my own century here in Midcoast Maine two weekends ago. I used some familiar roads and discovered some great backroads I had never ridden on. The highlight was seeing the Alewives heading upstream to spawn at a fish ladder in Newcastle. Three water bottles were enough since it wasn't too hot. Bathroom stops were mostly behind trees and buildings, although I did stop at two gas stations for some food. It was a great, hilly ride--I'm super lucky to live in a beautiful area!
David