The Honolulu Authority for Rapid Transportation (HART) has started column work on the regional elevated rail line in Hawaii, US.
The column to be built is located in the freeway medians at the H-1 Waiawa interchange between Waipahu and Pearl City.
HART also plans to build several support columns before guideway construction begins later this year.
HART CEO Dan Grabauskas said: "Rail construction continues near the H-1/H-2 Freeway area with the first support column going up for the planned rail guideway.
"We ask the drivers for their continued patience and understanding during the work and to be mindful of our crews stationed along the freeway."
The elevated rail line will link the Leeward Community College and Pearl Highlands train stations.
In June, HART announced the completion of first 100 support columns of its planned elevated rail system.
The authority aims to complete 220 columns by the end of this year, which will support the elevated guideway for the first ten miles of the rail route.
The first ten miles of the rail system from East Kapolei to Aloha Stadium will open in 2017, while the full 20-mile line is expected to open in 2019.
Image: HART begins column work along H-1 Waiawa Interchange. Photo: courtesy of Honolulu Rail Transit.