From the depths of a volcano to the density of a forest, people around the world are preserving natural wonders in their home cities. A docent at Mount Vesuvius shares why he has devoted his life to the volcano that destroyed much of the area in previous generations. A man in Hong Kong leads neighbors in a fight to preserve a historic forest that has become polluted.

Videos produced by RAI in Naples, Italy and RTHK in Hong Kong.

Great water demands require greater water solutions to keep big cities afloat.

Water activists combat climate change and illegal wetland development that is causing towns to flood in Argentina. Graciela Capodoglio founded the Natural Reserve of Pilar to preserve the floodplain ecosystem in the province of Buenos Aires.

In Mexico City, citizens formed an organization using innovative education models and technologies to address the city’s water shortage issues.

Videos produced by Construir TV in Argentina and SPR in Mexico.

Urban planners and average citizens around the world are working to improve transportation in congested cities. In Bangkok, an architect fed up with his daily commute studies the combination of traditional boats and modern trains to beat traffic. In Bogota, a professor and his students develop a citywide electric car sharing system to ease congestion in dense urban areas.

Videos by Thai PBS in Thailand and TAL in Colombia. 

Maintaining a sustainable way of life through organic farming is possible — even in big cities. In this episode, a woman in the favelas of Rio de Janeiro shows us how to maximize every last bit of local produce, while urban dwellers and beekeepers in Paris are developing a culture of sharing in rooftop gardens.

Videos produced by TAL in Brazil and QLM in France.

The heart of many large cities lies in their historic neighborhoods but across the world, the cultural vitality of these neighborhoods is threatened by the forces of gentrification and aging infrastructure. Hear from the people of Boyle Heights in Los Angeles and the Old Quarter in Hanoi, Vietnam as they work to improve and preserve their communities.