That's fair. So let's trim back the numbers a bit. According to TVO's website:
Originally Posted by TVO
Ninety per cent of the Ontario market accesses TVO through cable and satellite, and 10% of households capture the TVO signal over-the-air. Our broadcast distribution includes 23 major transmitter sites and 150 low-power rebroadcast transmitter locations throughout Ontario.
So let's leave the low-power relays off the table.
That's 23 high- and medium-power OTA transmitters — a more manageable target anyway.
Wikipedia lists them as serving the following communities:
Belleville, Chatham, Cloyne, Hawkesbury, Huntsville, Kenora, Kingston, Kitchener, London, McArthur's Mills (Bancroft), North Bay, Ottawa, Owen Sound, Parry Sound, Pembroke, Penetanguishene, Peterborough, Sault Ste. Marie, Sudbury, Thunder Bay, Timmins, Toronto, Windsor.