The route they use is pretty good for indoor runs when the weather or slush/ice gets bad. Mix of stairs + flat stretches. The only downside is that parts of the route are gated by doors which you have to open manually, but def a first world problem.

The route has several 180 degree turns. see https://www.bougebouge.com/wp-content/uploads/2024/04/captur... [edit: pic is shown at the bottom of https://www.bougebouge.com/en/shop/events/5km-bougebouge-tor... page]

Plus, like any other person using the PATH, the runners got lost along the way.

see https://runningmagazine.ca/the-scene/torontos-underground-5k...

It's the first year that they had the 5K run.