For nearly two decades, every East German carried a picture of this place. The ten-mark note of the 1971 series had Clara Zetkin on the front — socialist and campaigner for women's rights — and on the back, a woman engineer at a control console. The console was real. It belonged to the Kernkraftwerk Rheinsberg, a small Soviet-designed reactor set among pine woods and glacial lakes seventy kilometres north of Berlin, and the state was proud enough of it to fold it into the money.
The project began in 1956, at the height of the international enthusiasm for atomic power, and construction started on New Year's Day 1960. What went in was a VVER-70 — a Soviet pressurised water reactor, one of the first generation of demonstration plants, the ancestor of a design line that would eventually run across half of Eastern Europe.
The reactor went critical for the first time on 11 March 1966, unpressurised. Full start-up followed on 9 May, and commercial electricity began flowing on 11 October. The numbers were modest and honest: seventy megawatts gross, eight of them consumed by the plant's own systems, leaving sixty-two for the grid. Operating experience pushed the gross figure to seventy-five and then eighty. Over its life the station logged 130,000 hours of running time. It was never a workhorse of East German power supply. It was a school — the place where a country learned to run a reactor before it built bigger ones at Greifswald.
The site sits between two lakes, and one of them is famous. Theodor Fontane, born up the road at Neuruppin, gave his last novel the title Der Stechlin when it appeared in 1898 — a book about an old Brandenburg nobleman and a slowly, reluctantly changing world, named for a lake that at 70 metres is the deepest in Brandenburg and was long celebrated for water you could see eleven metres down through.
The plant drew its cooling water from the neighbouring Nehmitzsee and returned it, warmed, into the Stechlin through a purpose-built channel. For twenty-four years the lake ran hotter than it should have, and its plants and animals responded. That turned out to have a strange side benefit: the Neuglobsow research station on its shore had been taking limnological measurements since the 1950s, before the reactor started, which meant Germany acquired an unusually long continuous record of what happens to a deep, clear lake when you warm it. Since 2010, algal growth and oxygen loss have clouded the water again — a different problem, in a warmer century.
The worst accident in the plant's operating life came in 1973, when a tear opened in tubing in a cooling circuit. It was spotted quickly and repaired, and it was later classified as a level-2 event on the international nuclear scale — an incident, not an accident, well short of anything that threatened the surrounding country. In a state that did not discuss such things, it was nonetheless discussed for decades afterward.
In 2011, Deutschlandradio Kultur made a radio play out of it. Rheinsberger Restlaufzeit — roughly, Rheinsberg's Remaining Runtime — braids a fictional story together with original recordings of the plant's former spokesman reconstructing what happened that day. It is a peculiar and rather moving artefact: a decommissioned reactor's public voice, played back, trying to account for a morning nobody outside the fence knew about at the time.
Rheinsberg had been designed for a twenty-year life, to 1987. Renovation work bought it an extension in 1986, out to 1992. It got neither. On 1 June 1990 the last government of East Germany — three months from ceasing to exist — shut the station down permanently on safety grounds. Of all the decisions taken in that strange interval between the Wall and reunification, it was one of the quietest and most final.
Dismantling began in 1995 and is still going, run by Energiewerke Nord, the company that had operated the plant in its working life. Radioactive material has been moved into interim storage at Lubmin. The bill, once estimated at a billion euros, had climbed to roughly one and a half billion by 2025. Groundwater beneath the site is contaminated, and the buildings turned out to be more contaminated than surveys predicted, which pushed the schedule out toward 2040 or later. When it is finally gone, the ground will either be returned to green or turned into an industrial park — a decision nobody has to make yet.
What remains for now is the odd spectacle of Brandenburg's clearest lake, Fontane's lake, with a reactor beside it being unbuilt one careful piece at a time.
The site lies at 53.15°N, 12.99°E, about 8 km northeast of the town of Rheinsberg and roughly 75 km north-northwest of Berlin. From the air it is unmistakable in an otherwise unbroken carpet of pine: an angular industrial complex on the narrow land between the Nehmitzsee to the west and the Großer Stechlinsee to the east, with the straight artificial discharge channel running toward the Stechlin still visible. The Stechlinsee itself is the landmark — a large, deep, dark, roughly triangular lake with strikingly clean shorelines and almost no development, ringed by the Stechlin-Ruppiner Land Nature Park. Rheinsberg town and its palace sit southwest on the Grienericksee. Fly at 2,000–3,500 ft AGL; the decommissioning site is an active industrial facility, so check current charts and NOTAMs for any restrictions before overflying. Nearest fields: EDAX (Rechlin-Lärz / Müritz Airpark) about 25 km northwest, EDBK (Kyritz) roughly 45 km southwest, EDDB (Berlin Brandenburg) around 95 km south. Calm autumn mornings give the best water clarity and the sharpest reflections off the lake chain.