Millions visit the German capital each year. To ease the burden, Berlin is promoting green tourism, with solar boat trips, eco-hotels and sheep-mown parks.
00:01It's a highlight for many visitors to Berlin, exploring the city by boat.
00:07But the solar suncat is a little special.
00:10With zero emissions, it glides silently along the river Spree, powered only by the sun.
00:17Boat owner Louisa Ahrens first had the idea in 2010,
00:21when looking for an alternative to the large diesel-powered vessels.
00:26She says they consume up to 40 litres of fuel per hour.
00:31I've always enjoyed being on the water, so of course I loved this idea.
00:37And that motivated me to push ahead with it.
00:40I couldn't understand why the world wasn't doing this all the time.
00:44Solar-powered boats don't damage the shoreline, they don't smell, they're silent.
00:48So I didn't get why they weren't being used.
00:52Features like these make Berlin one of the most sustainable tourist destinations worldwide.
00:59More on that later.
01:01Meanwhile, a group of US students from Massachusetts are exploring the trendy district of Kreuzberg.
01:09The Kverstadt-Ein Association offers city tours featuring personal stories on themes like homelessness or migration driven by climate change.
01:19City guide Mohamed Lamine Jadame was born in Gambia.
01:24He's lived in Berlin for over ten years.
01:27In his homeland he saw fishermen returning home with ever smaller catches,
01:32and farmers harvesting less and less due to droughts.
01:35Now in Berlin he's observed a very different way of life.
01:38He says everything is connected.
01:40The connection is that when I came to Berlin I was kind of surprised in a sense of over consumption.
01:49And all these waste mostly end up in my country where I came from.
01:56And to get rid of those waste materials people just bone them or throw them into the river.
02:03The German capital is home to just under 4 million people.
02:07So when 13 million visit the city like last year, it's a lot.
02:122024 saw 30 million overnight stays. Nearly half of those visitors come from abroad.
02:21Despite the crowds, Berlin has moved up to fifth place in the Global Destination Sustainability Index for megacities and metropolises.
02:33GDSI is a ranking system created by an association of international travel destinations.
02:42The association has set a goal to make its location sustainable in terms of tourism and event management.
02:49So it basically measures the sustainability performance of a destination.
02:54By measuring how sustainable the hotels are, for example, this one scores well.
03:01The Vienna House in East Berlin offers charging stations for electric vehicles and has its own repair workshop.
03:08Admin is largely digital, which saves paper.
03:13There's a beekeeper who keeps bees in the inner courtyard.
03:19They supply the honey for the hotel's breakfast buffet.
03:23Leftover buffet food is sold at a low price via an app to avoid food waste.
03:29I like to save it from being thrown away.
03:32So it's much better for the environments than for other people who share with friends.
03:38Visitors looking for a place to stay in Berlin can search specifically for eco-hotels or other sustainable accommodations.
03:47Ten kilometers south of the hotel lies Tempelhofer Feld, a former inner city airport.
03:54The last plane took off from here in 2008.
03:57The 300-hectare complex was then opened for Berliners and tourists.
04:02Some new residents have also moved in.
04:04Plains have given way to sheep.
04:08Around 100 animals grazed the area to protect the skylark, a rare bird that only breathes on the ground.
04:19Lawn mowers would destroy their nests.
04:22Sheep now graze in several of Berlin's parks.
04:25They've become a tourist attraction in their own right.
04:29During the long day of urban nature festival, we demonstrate sheep shearing.
04:37There are dates throughout the year when people can see the sheep up close.
04:41But Tempelhofer Feld offers daily access all year round.
04:45But it's not all idyllic.
04:51Litter is a problem throughout the city.
04:54Every year 45,000 tons of waste end up on the streets of Berlin.
04:59Discarded coffee cups are especially plentiful.
05:03A long-term study by Humboldt University in Berlin found that people feel that litter from single-use products is the biggest blot on the landscape in major German cities.
05:16Even more than dog poop.
05:17And 40% of the garbage in public trash cans is single-use packaging.
05:22Pilot projects are addressing the coffee cup issue with deposit machines.
05:28If users return the cups, they get money back.
05:31However, the machines are still few and far between.
05:34The US students are also getting the message that more needs to be done.
05:40The tour has got many of them thinking.
05:43In their conversations with tour guide Mohamed, many are starting to see the bigger picture.
05:49It makes you almost feel a little guilty.
05:53And I think it makes you feel more conscious of your lifestyle.
05:57Before you buy something, before you throw something away, to always be more careful.
06:03To understand that it does have effects on people around the world.
06:06It's like the butterfly effect at the end of the day.
06:08What you do in one side of the world will affect another part of the world.
06:12It's like if you go to a friend's house and then you trash the common room.
06:16Everybody lives in the same place and it will affect eventually everybody.
06:20Not something passengers on board the boat appear to have thought of.
06:25Most of them told us that their choice of a solar powered boat was just a coincidence.
06:31It seems sustainability is becoming something many people take for granted.
06:36The fleet now has three solar boats.
06:39All of them are fully booked during the summer season.
