Mexican tourist Rocio Gomez spent an hour boating on Copenhagen's canals free of charge in exchange for picking up trash in the water, part of a city program for rewarding eco-friendly tourists.

On a trip to Copenhagen, I rented a kayak with a friend and picked up trash from the city's harbor. We rented a kayak for free through GreenKayak, an environmental NGO that operates in five countries.

Ingrid K. Williams is a regular contributor to the Travel section. She lives part-time in Stockholm and has covered Scandinavia since 2010. For decades, Copenhagen has been lauded for its design ...

With a rich culture and history, impeccable dining scene and relaxed pace of life, spending 2 days in Copenhagen is a must during your next European summer adventure! It’s the capital of Denmark ...

A version of this article appears in print on , Section RE, Page 7 of the New York edition with the headline: On Copenhagen’s Harbor, a Modernist’s Dream. Order Reprints ...

During a wet and dreary afternoon, 40-year-old Alana strutted along the harbor city’s coastal path in an outfit determined to conjure visions of summer amid the gray weather.