The 510 Spadina streetcar was forced to turn back on part of its route early Wednesday after a driver drove into the Queens Quay tunnel and travelled about 600 metres all the way to Union Station.

The incident began just after 2 a.m., said TTC spokesperson Stuart Green, when the compact SUV made it past the gate, flashing lights and rumble strips installed in 2018 to prevent just such incursions from happening.

It's believed that the vehicle was "tucked in closely behind the streetcar" and that's how the driver was able to avoid the automatic gate before it closed.

He then followed the streetcar more than half a kilometre, through Queen Quay Station and into Union Station, where he got stuck on an elevated concrete pathway that streetcar operators use to reach a bathroom.

"It's hard to know where they thought they were going or how they thought that was a roadway. It's clearly marked that it's not a roadway, it's gated," Green said

The driver remained on scene and spoke to Toronto police, Green said.

And here's what an SUV stuck on the Union Station streetcar platform looks like. The concrete block is a walkway to the operator toilet. <a href="https://t.co/7CQOt5oRpW">pic.twitter.com/7CQOt5oRpW</a> —@TTCStuart

TTC crews used heavy equipment to tow the vehicle out of the tunnel, he added. There was no damage to the tracks and service on the 510 Spadina and 509 Harbourfront routes resumed around 6 a.m.

Green said that, since 2014, there have been about 26 such incidents in the tunnel. The automatic gate was finally installed in October 2018, and this was the first driver to make it into the tunnel since then.

"We're sort of hard pressed to think of any other measures we can take at this point, short of closing the tunnel and that's not an option," Green lamented.

"Hopefully it doesn't happen again."