Castle Frank Brook, which was also known as Brewery Creek or Severn Creek, rose in three small streams in the Dufferin & Lawrence area and flowed through the Cedarvale, Nordheimer, and Rosedale Valley Ravines, to enter the Don River south of the Prince Edward Viaduct. It gets its name from Castle Frank, the summer residence of Sir John Graves, and Lady Simcoe, which they named for their son Francis. It was approximately twelve kilometres long and had another twelve kilometres in tributaries. Castle Frank Brook is divided into five reaches in this account. Fairbank Reach starts in the Lawrence Avenue / Dufferin Street area and stretches through the former Cities of North York and York to Cedarvale Park near the community centre. Cedarvale Ravine Reach includes Cedarvale Park and the Cedarvale Ravine down to St. Clair Avenue West. The Third, Nordheimer Ravine Reach, runs from St. Clair Ave. West to the CPR tracks Davenport Road). The Fourth, the Yorkville Reach, continues from the CPR through the former Village of Yorkville to the Sherbourne Street Bridge. The Fifth, Rosedale Valley Reach, follows the ravine to The Don River. Several tributaries are also described including: Parsons Stream, Barker Stream, Cedarvale Stream, Forest Hill Stream, Fry Brook, Mashquoteh Creek and Lamb’s Creek.