The streetcar that chugged up and down the steep grade along Queen Anne Ave started operating on overhead-wire electricity in 1900, but it still needed some help to manage the hill. So engineers designed a system of counterweights – a 16-ton train that ran in a tunnel beneath the street would go up when the cable car went down and vice versa.
The cable cars were retired in 1943, but the underground tunnels are still there (although they're not currently open to the public). Those looking to tone their legs can climb the grueling hill that the counterbalance helped haul streetcars up.
