Well designed transit maps are a rare thing these days. I was really surprised to discover that one of the best I’ve seen for a long time comes from Ukrainian.
I believe that Travel By Rail is one of the best transit maps out there. It visualizes the number of intercity train travels between every two cities in Ukraine, as well as Russia and Belarus. It is complemented with graphs visualizing temporal distribution of train journeys.
You can click on each city to explore journeys from a given location. You can also select a range of dates on a graph to analyze the data for a given time.
Really interesting and well designed project.