Featured Photos – February 19
198 piles (support columns) form the perimeter box of the Central Subway Project’s Union Square/Market Street Station. When open for revenue service in 2019, the underground station will be a transfer point for 38,000 daily riders.
![140710_1007_UMS](http://www.centralsubwayblog.com/blog/wp-content/uploads/2015/02/140710_1007_UMS.jpg)
This machine creates a core for installation of concrete piles, which are external support columns that make up the outside walls of the Metro station.
![Piles are external support columns that create the exterior walls of the Metro station. Construction crews recently finished pile installation for the future Union Square/Market Street Station. These piles will be underground on Stockton and span between Geary Boulevard and Ellis Street.](http://www.centralsubwayblog.com/blog/wp-content/uploads/2015/02/141015_1045_801Market-682x1024.jpg)
Construction crews recently finished pile installation for the future Union Square/Market Street Station. These piles will be underground on Stockton Street and span between Geary Boulevard and Ellis Street.