"Horse-drawn carts were the first trains, predating the steam-powered variety by about 200 years. Horse-drawn trains were first used on wooden tracks to transport coal away from coal mines. Similar tracks were soon built to link neighboring towns, and the vehicles began transporting people as well as goods. The trains moved as slow as 10 kilometers per hour (6 mph), yet they were more reliable and comfortable than horse-drawn carriages on bumpy roads".
Looks like they are replacing some of the raised log sidewalk. You can see it better across the street, under the shingle sign. I guess it kept the water underneath.