There's a big subway closure this weekend in Toronto, which will shut down a huge part of Line 1, between St. George and Sheppard West (the station formerly known as Downsview).

Why is a key part of the transit shut down? To bring in Automatic Train Control.

The TTC is re-signaling the line, which will enable more trains to run at the same time. As the Globe and Mail reports, the goal is to have 32 trains speeding along at once - there are currently 25.

With Automatic Train Control, "Train speed and separation between trains will now be controlled automatically rather than being human controlled," explains the TTC. According to the Globe, there will still be staff on board to ensure everything's running smoothly.

The Globe says the system will start to be rolled out this fall, but it won't all be complete until 2019.

And remember, if you're trying to get anywhere this weekend, the DVP and the Gardiner are also closed on Sunday!

Correction: The original title of this post has been changed to reflect the fact that TTC subway trains will not be driverless once Automatic Train Control is implemented. Staff will still have the ability to manually override the controls.