No wonder I spend so much time on this forum

I have a similar dilemma:

1) calculate times taken to travel between various points by ferry in an imaginary city in a far away country
2) read every single post on this forum

As a geek, I feel obligated to suggest that you write a program that creates a weighted graph and applies Dijkstra's shortest path algorithm. It'll take more time than doing the calculations manually, but so much more fun.