When a house is scheduled for demolition, sometimes the owner will donate the old structure to the local fire department for training. A fire will be set and a crew will go into the burning house and put it out. Another fire is set in a different room, and it too put out. And so on for as long as the structure is reasonably safe to enter. Then the building is allowed to burn completely. This process of repeated setting and extinguishing allows as many firefighters as possible to get involved.
This gallery was originally posted way back in 1998 on one of my earliest websites. I've finally gotten around to rescanning the original 35m slides and adding many more to the galley.