The "Femeiche" oak tree in North Rhine-Westphalia may well be the oldest living tree in Germany, dating from the first millenium AD. (video copyright dpa)

These days, a lot of people are paying attention to their carbon footprint. Drinking straws are no longer made of plastic, toothbrushes are made of wood, and we're happy to forego that domestic flight to Munich for a long weekend—all for the sake of the environment. But there's one person who doesn't care: Felix, a rabbit from a children's TV series.

Jannika from "ZDF Magazin Royale" has to give Felix the Rabbit a piece of her mind. All of his traveling is no longer sustainable given its impact on climate change!

EFF is a collaboration between singer Mark Forster and DJ Felix Jaehn. The song "Stimme" has a positive message about trusting yourself.

From Brussels to Barcelona in just 30 minutes? The dream could soon become reality! Come along on a high-speed trip to the Netherlands and learn more about the futuristic vision of a Europe-wide Hyperloop transport network.

Bjørn Dunkerbeck is the greatest legend windsurfing has ever produced—surpassing even his long-time rival and now friend, Robby Naish. RTL reporter Laura Pröscholdt went to visit him and his family on Gran Canaria and learned: Windsurfing keeps you young!

In this part we learn more about Björn's family and what influence they had on his career as a professional windsurfer.

This part is about how windsurfing has changed throughout the years. Björn Dunkerbeck talks about new sports, his own goals, and why today it's mainly his sons who compete in the harsh conditions.

The first segment introduces us to the main characters who, aboard the train from Munich to East Berlin on August 13, 1961, will face a difficult decision: freedom or home.

August 13, 1961: A fateful message reaches the train bound for East Berlin: The construction of the Wall has begun. The passengers now have three and a half hours to decide—home or freedom?

As the train continues its course towards Berlin, the band of musicians perform a song about yearning for freedom, which contrasts with the security checks of East Germans returning from the West.

As the train makes its way along, a reporter comes to interview Edith Salzmann, a locomotive driver. Through them, we get an impression of the roles and daily life of people in East Germany.

The news of the Berlin Wall's construction continues to spread throughout the train. Arthur and Andi finally find what they have been looking for all this time.

Elke repairs the radio in the compartment and everyone hears the news: A wall is being built through Berlin and along the state border to seal off the Soviet zone.

In the inter-zone train to East Berlin, people listen to the distressing radio reports. At the same time, we get insight into the lives of other people on this August 13, 1961 - the day when the Berlin Wall is erected and begins to separate its residents from the rest of the world.