The Seoul Metropolitan Government will plant some 24,000 trees in the new elevated park that was once a drab flyover next to Seoul Station.
Dutch architect Winy Maas is designing the park, while his colleague Ben Kuypers is in charge of landscaping.
The park, modeled on New York's hugely successful High Line, opens in April. The 1 km path meandering through the park has been given the official name Seoullo and will be lined with 24,085 trees placed in alphabetical order according to their genus.
Koh So-young at the city government said, "We want pedestrians to become familiar with the names of the trees as they walk down the path."
Over 600 tree beds have their own drip irrigation and are designed to keep the water and roots safely in. The trees are being brought to Seoul from 27 farms across the nation. City officials and others involved in the project scoured around 100 arboretums and plantations across the country since April of last year to look for them.
The city government spent around W600 million buying the trees (US$1=W1,168). The most expensive is a pine that costs W3 million. They will be lit up by sparkling LED lights at night.
The flyover park will contain two main flower gardens and 14 smaller rest areas. Six elevators will be installed to ensure easy access for the elderly. There will also be three transparent floor panels to offer visitors a vertiginous view of the traffic below.
Four terraces are being built at the most scenic points. The park will also house cafés, trampolines, a puppet theater for kids and other facilities.
The park is the brainchild of Seoul Mayor Park Won-soon, who announced it in May 2014 and hopes it will increase pedestrian traffic to the Seoul Station neighborhood and boost commerce. Critics have accused him of using the project as leverage for his presidential ambitions at the cost of potentially snarling traffic in downtown Seoul.
Former president Lee Myung-bak, who served as Seoul mayor from 2002 to 2006, hugely boosted his popularity when he freed the Cheonggye Stream, now a much-loved landmark in the city, from the miserable road that had been built right on top of it.