Like Belém's Museu da Electricidade, the Water Museum and its contents are important parts of Portugal's industrial archaeology and still run by a utility firm - in this case, state water company EPAL. Housed in the first main pumping station to serve Lisbon, the museum is dominated by four huge steam engines from the 1880s, formerly used as pumps. One is set in motion every month or so. The rest of the displays trace the history of Lisbon's water supply from Roman times to the present.