Copenhagen's new Metro is a thing of beauty

Ever since bicycles were imported into Denmark from France in 1869, they have become the main form of transportation in the Scandinavian city. In the 1920s, it wasn't unusual to see both the working class as well as high society pedaling through the streets. But with the opening of the Metro's new M3 Cityring line, commuters have a new way of getting around.

While Copenhagen's Metro has always been rather efficient, many neighborhoods lacked stations, and thus, accessibility.

In addition, a growing population of about 10,000 new residents per year is taxing the buses and trains already in circulation. In a city of 650,000 people, about 200,000 commute on the Metro daily, sometimes in conjunction with a bike during their journey.

Cityring, a 15.5-kilometer (approximately 9.63 miles) circular line with 17 new stops — which nearly doubles the number of existing stations — now connects outlying neighborhoods that radiate far from the city center. Residents won't need to rely on their bikes to get around, a boon especially during Copenhagen's hygge-inducing winters.

The impetus for the project was twofold, according to Henrik Ploughmann Olsen, CEO of Copenhagen Metro. "First of all, it was a question of improving public transport, making it more efficient and of better quality," he said. "But it was also about city development in other areas outside of the city center."

Public squares were constructed, with 150 benches and 800 trees, were installed around the 17 new stations. The plazas not only allow access to the Metro, but will hopefully encourage more commerce and housing.

"We see that it attracts shops but also offices and service-oriented businesses," said Olsen.

Building the line was not without its challenges.

Olsen acknowledged that the eight years of construction impeded traffic and generally disrupted people's daily lives. "We had the machinery right outside people's windows for quite a substantial number of years," he said.

Technical issues also challenged tunnel designers. They had to build around older structures with shaky foundations, such as the historic Frederik's Church, a.k.a. Marble Church, at the Marmorkirken station.

Controlling groundwater was also imperative during construction.

"A lot of the houses in the inner part of the old city center are actually founded on wooden piles from the 17th century or 18th century," explained Olsen, "If you remove the groundwater from those piles, they'll rot."

In addition, builders had to deftly maneuver around existing Metro tunnels--but Olsen proudly notes the extension was completed without causing any shutdowns to the current system.