What's inside that big building at the Chestnut Hill Reservoir?

CHESTNUT HILL - In the upscale village of Chestnut Hill, the home of the Boston Marathon's Heartbreak Hill, there's a building near Boston College that catches your eye.

"It really was the pride of Boston"

It's the Metropolitan Waterworks Museum , next to the Chestnut Hill Reservoir.

"When this opened to great fanfare in 1888, it really was the pride of Boston," Eric Peterson, the museum's executive director, told WBZ-TV.

The 13-year-old museum houses three massive steam engines that were critical to the growth of Boston during the Gilded Age of the late 1800s and early 1900s.

"They needed water pumped up," said Peterson. " So how do you get water up? You use giant steam engines to do it."

The engines would pull water from the reservoir, then pump it to Fisher Hill Reservoir in Brookline, which has since been filled in. From there, it supplied neighborhoods like Beacon Hill.

"Prior to that time, you would have seen people going up and down the hill to get their water from down below with buckets, essentially," said Peterson.

30 million gallons of water a day

At its peak, the engines pumped 30 million gallons of water a day into the city. Despite their massive size and capabilities, the pumps were deemed obsolete and decommissioned in 1980. The building was left abandoned until it was redeveloped and reopened in 2011.

"There's no other engines in the world, except this left," said Peterson.

The beautiful brass and wood machines, full of valves, dials and pipes, now stand as testament to Boston's ride as an industrial power. The museum is free and open to the public Wednesdays to Sundays, from 11 a.m. to 4 p.m. Special access tours that go up on the engines cost $18.