Seoul Waterworks Museum (Ttukdo Water Purification Plant)

At the southern tip of Seoul Forest, beside the Gangbyeon Expressway, stands a red-brick building. This is the Ttukdo Water Purification Plant No. 1, which sent Seoul its first tap water in 1908 and now houses the city's Waterworks Museum. Entry is free, and you can explore the pump house with its granite arched porch and, hidden under a lawn, the slow sand filters, the oldest reinforced concrete structure surviving in Korea.

History: from the Han River to the tap

In 1903 two Americans, Collbran and Bostwick, obtained a waterworks concession from the government of the Korean Empire. Construction of the plant began in 1906 and finished in 1908, with all machinery and materials imported from Britain and the United States. Supply started on 1 September 1908 to the area inside the city gates and to Yongsan, marking the start of modern waterworks in Korea.

The plant initially treated 12,500 m³ a day, enough for about 165,000 people and 32% of Seoul's supply at the time. Stones set either side of the entrance read "Gyeongseong Waterworks Pumping Plant" and "Built in the 11th year of Gwangmu", dating the pump house to 1907. The pump house and the slow sand filters were listed as Seoul Tangible Cultural Heritage in September 1989.

What to see

• Main hall (former pump house): the red-brick building at the centre of the grounds once pumped treated water up to Daehyeonsan reservoir. With its granite arched porch and round-arched windows it is a Renaissance-style piece of early modern architecture. Inside, an exhibition traces a century of Seoul's water supply.
• Slow sand filters: what looks like a broad lawn hides the beds where river water once seeped slowly through layers of sand and gravel. Six basins survive, each 21.2 × 35.1 m, and they are the oldest reinforced concrete structure left in Korea.
• Annex (former intake pump house): it drew raw water from a point 166 m out towards the Han River and now hosts a new special exhibition every year.
• Water and Environment Hall: built on the site of the old staff quarters, it covers the wildlife of the Han and the water cycle.
• Outdoor displays: pipes, pumps and valves used from the 1920s to recent times, plus a hands-on area with a well, buckets, a hand pump and a communal tap.
• Zelkova tree: a zelkova in the grounds was declared a protected tree in 1982, when it was already about 300 years old.

A museum next to a working plant

Right next door, the Ttukdo Arisu Water Purification Centre still produces Seoul's tap water using advanced treatment, and can be visited on a guided tour booked in advance. Seeing a pump house from more than a century ago beside a modern plant still at work is what makes this museum unusual.

Tripto tips

• Opening hours: 09:00–18:00. Closed on Mondays, 1 January and on Seollal and Chuseok days.
• Admission: free, and individual visitors need no booking. Guided tours of the exhibitions and visits to the purification centre are booked through the Seoul Public Service Reservation system.
• Time needed: a little over 1 hour for all the halls; add a walk in Seoul Forest for a half-day outing.
• Getting there: from Seoul Forest Station, exit 3 (Suin-Bundang Line), walk about 300–400 m along Wangsimni-ro towards the Gangbyeon Expressway to the main gate, or follow the signposts from the southern end of Seoul Forest.
• Best time: spring blossom and autumn colour in Seoul Forest make good pairings; on rainy days the indoor halls still fill a visit.