Bad Erna, Recreation area in Elbe-Elster District, Germany.

Bad Erna is a recreation area around five artificial lakes formed from four former lignite pits about 4 km south of Doberlug-Kirchhain, in the Naturpark Niederlausitzer Heidelandschaft. The lakes are named Inselteich, Welsteich, Blauer See, Barschteich and Franzosenteich; the main bathing lake is the Inselteich, watched by a lifeguard and closed to motorboats.

The five lakes were created from four former lignite pits, among the first open-cast coal mines in Lower Lusatia, worked until around 1900. The area was named after the Erna pit and opened to the public for tourism soon after. In 1928 the town of Dobrilugk bought the land from the municipality of Lindena, and around 1930 the first bungalows, a restaurant and a boat rental appeared at the Inselteich.

The name Bad Erna comes from the former Erna pit, and the five forest lakes are individually named Inselteich, Welsteich, Blauer See, Barschteich and Franzosenteich. Around the Inselteich, roughly 250 weekend cottages and bungalows are privately owned and leased long-term, a cottage culture dating back to the first bungalows of the early 1930s.

The main bathing spot is on the Inselteich, which has a lifeguard on duty and a guesthouse; motorboats are not allowed on this lake. Around 250 weekend cottages and bungalows stand on the shore, privately owned and leased long-term. A volleyball court sits by the water, and the Blue Lake, Barschteich and Franzosenteich are reserved for angling.

The five lakes were dug from four former lignite pits that operated until around 1900, among the first in Lower Lusatia. At the Welsteich, remains of an old briquette factory can still be seen. The northern Hammerteich, formed by digging bog iron ore, is used for commercial fish farming.