The Merchant Ale House & Brew Pub is located at 98 St. Paul St. in St. Catharines, Ontario.

Here's a link to the MapQuest Map.

From Toronto:
Exit Q.E.W. at Ontario St.
Head South on Ontario St. to St. Paul St.
Left onto St. Paul St., The Merchant is two blocks up at Queen St..

From Niagara Falls:
Exit Q.E.W. at Lake St.
South on Lake St. to the end.
Turn left onto Ontario St.
Left onto St. Paul St.
The Merchant is one block up.