The TTC is still doing signal upgrades on the Yonge-University-Spadina line, and so this weekend, like many before it, will be made just a little livelier by a partial subway closure.
This time, the affected bit is the stretch between Bloor-Yonge and Union stations. That whole chunk of track will be closed on both Saturday and Sunday, though there will be frequent shuttle buses running between Rosedale and St. Andrew stations.
If all you want to do is get to Union Station, you’ll still be able to ride the subway down from St. George station. More details about the closure are in the TTC’s press release.