The Toronto Waterfront Marathon just announced they'll be expanding the event to run over two days this year, but that could mean traffic headaches for the city.

The TCS Toronto Waterfront Marathon is coming up this October, and will — like every year — include a 5K run and half-marathon as part of the festivities.

Diverging from past years, though, the organization recently announced via a Facebook post that they'll be moving the 5K to take place on the Saturday prior to the half- and full-marathons on Sunday, "making [their] marathon weekend a full-fledged racing extravaganza!"

"With the Marathon and Half Marathon following on Sunday, October 20th, we're bringing you a true "Event Weekend" experience similar to major marathons around the world," the post reads.

The 5K will on University north of Queen before heading south to Wellington, east to Bay, south to Lakeshore, and loop back along Rees before heading north to the finish line at Nathan Phillips Square.

While the marathon, being an annual subject of complaint among drivers, is now extending road closures over two days, the good news is that the 5K will close fewer roads, for a shorter period of time. 

The 5K is set to kick off at 9 a.m., with runners gathering at the starting line at 8 a.m., and must be completed within an hour and 10 minutes, so road closures on the first day of the weekend shouldn't last past noon, though the TCS hasn't yet confirmed the duration of road closures.

The TCS Toronto Waterfront 5K will be taking place this year on Saturday, Oct 20 and the half- and full marathons will be held on Oct 21.