Each open truck pulled by horses was known as a tram. The rules of the tramway said that each tram was to weigh no more than two tons when full of coal. Three of these would make up a train pulled by two horses led by a driver or waggoner. The horses were changed regularly and an extra horse could be added to pull the trams up difficult inclines.
There were regular passing places on the tramway so that one train could pull to one side out of the way when two met. An empty train usually gave way to a full one.

The tramway approached Hay from Talgarth along the Wye valley. At Llwynau Bach near Glasbury there were stables for the horses and a coal warehouse. The tramway came into Hay along the Warren and went through the town on the river bank.
A little branch line went up a small incline to a wharf behind the old Cock Inn. Here the trams could be loaded and unloaded.
The old inn was rented by the tramway company for use as their offices, and here the clerks would record what goods were being carried and how much people had paid the company to transport them.
The company had a weighbridge in Hay so that they could weigh the trams and know exactly how much coal or lime was being carried.

A fatal accident on the tramway...