Writer and photographer Paul Kaye began a 2,230 mile (3,600km) cycle ride down the route of the Iron Curtain in the German port city of Luebeck. The path of a fence across the dunes can still be made out, 20 years after the curtain fell.
In the village of Rueterberg, overlooking the River Elbe, a disused watchtower has been converted into a summer home.
In some places, the Iron Curtain infrastructure has been preserved intact, as a reminder of the past. Here, in Hoetensleben, an archive photograph shows that nothing has changed.
Helga and Willi Grote enjoy evening strolls along the Kolonnenweg, a 1,400km-long military service road built by East Germany. There are plans to make the whole Iron Curtain into a long-distance path, the Iron Curtain Trail.
The Fulda Gap was regarded, in the West, as the most likely point for Soviet tanks to come charging across the Iron Curtain. A former US military watchtower stands barely a snowball's throw from its Eastern counterpart.
A bench stands as a memorial to the 1,000-year-old village of Erlebach. It stood too close to the border between East and West, so the East German authorities destroyed it.
Before 1989, this watchtower on Erna-Berger-Strasse near the Potsdamerplatz in central Berlin surveyed a desolate buffer zone. Today it is surrounded by new buildings in one of the busiest parts of the city.
At Liesenstrasse, an overgrown section of the Berlin Wall remains as a reminder of the time of division.
But at Dreilinden in the south of Berlin, the asphalt belonging to a checkpoint - where once cars travelling out of West Berlin towards West Germany were inspected - is being reclaimed by the surrounding Dueppel forest.
On a hill on the western edge of the Czech Republic lies an abandoned radio receiving station. The tower was one of a string of installations that allowed the Soviet bloc to monitor Western radio activity.
The Czechoslovak army used the remote Sumava national park, on the German border, for military exercises. Twenty years later, unexploded munitions are still a danger.
It was a tradition among Czechoslovak border guards at this quiet spot near Vranov nad Dyji to carve into beech trees the number of days service remaining before they could go home.
The fence bordering Czechoslovakia was not as formidable as the fence between East and West Germany, where automatic guns would fire at anyone attempting to cross.
More people died attempting to cross the former Yugoslavia's eastern border with the Warsaw Pact countries, than its border with Austria and Italy. This watchtower stands near Lipica on what is now Slovenia's border with Italy.
Paul Kaye lived in Bratislava in the 1990s and is now based in Brussels. His Curtainrider blog (link below) documents his journey from the Baltic to the Adriatic.
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