It's going to be complete mayhem on Toronto transit this weekend

GO and TTC subway closures this weekend will gnarl transit traffic, with the two transit agencies shutting down a combined 111 kilometres of tracks. In addition, a major road closure will cause traffic headaches and transit detours along a major Toronto thoroughfare.

Anyone relying on public transit in and around Toronto should take note of overlapping closures on local and regional rail networks during what is expected to be an especially busy first weekend of June in the city.

Two entire GO lines and a significant stretch of the TTC's busiest subway route will be out of service on Saturday, June 6, and Sunday, June 7, and here's everything you need to know ahead of the disruption:

TTC Line 1

The TTC plans to halt service on a roughly 11-kilometre stretch of Line 1 from St George to Sheppard West stations for the full day of Sunday, June 7. While this won't be a full-weekend closure, it will overlap with several other major GO outages and service reductions, which could amplify its impacts on riders.

Lakeshore East Line

Metrolinx is shutting down the entire 50.5-kilometre Lakeshore East Line this weekend for construction work, with GO buses to replace trains between Durham College Oshawa and Pickering GO, then run directly to the Union Station Bus Terminal in downtown Toronto.

Stouffville Line

The full 49.6-kilometre Stouffville Line will also shut down for this weekend due to planned construction along the route. Replacement buses will serve a portion of the line, but not stop at Milliken, Agincourt and Kennedy GO.

Lakeshore West Line

The Lakeshore West Line will be cut to 30-minute intervals this weekend between Oakville GO and Union Station and hourly intervals between West Harbour GO and Union Station.

UP Express

Planned track upgrades will require UP Express trains to operate on a modified schedule of every 30 minutes instead of the regular 15-minute intervals for this entire weekend.

Road closures

If the transit situation wasn't bad enough, the Do West Festival will shut down a portion of Dundas Street West, from Lansdowne to Ossington, from Friday, June 5 at 10 a.m., to Monday, June 8 until 2 a.m.