A group of children in Tram Village, Thuong Tin District flocks to the water each afternoon around sunset.
The lake was funded by Tram villagers, in need of a place to have fun and escape the heat after school or work.
Despite the shallow water, derived from the Red River, some swimmers still wear life vests as a precaution.
A boy brings a life saver which is an inflated old tire. Many parents said they prefer having their children come to the lake to swim after class, which keeps them away from the TV and video games.
In Sai Son Commune of Quoc Oai District, locals often flock to Long Tri Lake in front of Thay Pagoda to swim in the afternoon.
The water in Long Tri Lake is derived mostly from the rain and other natural sources. Locals said household wastewater is not allowed in the lake.