Let KAYAK do the searching
Based on KAYAK hotel searches, the most popular destination is Toronto (74% of total searches to Southern Ontario). The next most popular destinations are Niagara Falls (16%) and Ottawa (6%). Searches for hotels in The Blue Mountains (4%) are also popular.
KAYAK users have found double rooms in Southern Ontario for as cheap as $42 (Toronto) in the last 3 days. The average price is $396.