People will go green if it’s cheap and easy.Thirty-seven percent of Copenhageners commute to work and school by bike. Concrete dividers separate bicycle tracks from motorists so it’s safe, new cycling superhighways make suburb-to-city biking faster than crawling in traffic, and 40,000 public bike parking spots remove the need to shell out for the paid parking that you’ll find in much of the city.  Rooftops are the new frontier. Plant-covered roofs help keep rainwater from flooding streets and homes, while bare ones are increasingly being used for urban farming and beekeeping. In fact, Copenhageners kicked off the Green Capital year by writing messages about sustainability under the light of beeswax candles made from the wax of their city bees.   Going green isn’t a catchphrase; it’s a conversation. From industry-specific seminars where professionals can learn and share eco-friendly practices, to a playful exhibitions that mix toys with sustainability education for children at a local museum, creative approaches to environmental issues are celebrated. Progress takes careful planning, resources, and patience.Copenhagen’s harbour was full of sewage, algae, oil, and industrial waste 15 years ago, but thanks to an upgraded sewer system and wastewater treatment plants, it’s now crowded with swimmers all summer long. Up next? Becoming carbon-neutral by 2025. And they’ve already made progress: The bike-centric city has cut carbon dioxide emissions by 40% since 1995. More from Prevention: 70 Easy Ways To Be A Little Greener