This station did not open at the same time as the rest of the Harbourfront line it served, due to disputes regarding direct access to nearby businesses that eventually fell through.

Originally there was to have been an underground station in front of the Westin Harbour Castle Hotel and the Jack Layton Ferry Terminal.

The station was closed from July 2012 to October 2014 due to Waterfront Toronto's project to rebuild Queens Quay West and reconstruction of the Harbourfront streetcar line, during which time there was a replacement bus service.

In 2016, one automobile reached Union station despite the tunnel having no provision for rubber-tire vehicles, with streetcar tracks protruding from a shallow trench.

In April 2017, to prevent motorist invasions, the TTC made changes at the tunnel entrance by lowering warning lights closer to driver eye level, by placing a flashing light on a pole between the tracks, by adding rumble strips and by adding signs on posts that also narrow the passage to the tunnel.

[9] On April 22, 2018, the TTC added 6 new bollards at the east side of the intersection of Queens Quay West and York Street to obstruct drivers from driving onto the right-of-way and into the tunnel.

[10] Further, in late July 2018, the TTC installed two gates at the top of the ramp to the tunnel which can be opened in 3 seconds by a transponder on an approaching streetcar.