John and Magdalene Clendenen and their children were among the earliest settlers of Markham Township. Believed to be of Irish origin, the family settled here from New Jersey. The Clendenen family arrived in Upper Canada in 1797, initially living at 12 Mile Creek (St. Catherine’s) on the Niagara Frontier. John Clendenen Sr. petitioned for a land grant, and was assigned Lot 17, Concession 8, Markham Township in 1801. After clearing 18 acres and building a hewn log house, he received the Crown patent in 1803. Following John Clendenen’s death in 1815, the property was divided among his descendants.
The Adam Clendenen House at 8 Green Hollow Court (previously known as 9516 Ninth Line and as 9642 9th Line) is a 1½ story, red brick, farm house, built in the Georgian Style about 1840. The Family Burial Plot is located near the centre of Lot 17, Concession 8. Five grave-markers still mark the final resting place of the early Clendenen’s. The Clendenen family farmed this land until 1950. The early brick farmhouse built by Adam Clendenen (1809-1894), John and Magdalene Clendenen’s grandson, still stands today at 8 Green Hollow Court. In 2007, the House was completely restored and incorporated into the construction of the All Smiles Childcare Centre, designed to serve the children of Markham.
Although the lands around the House and the Centre are developing quickly, the Adam Clendenen House will serve as an important reminder of the historic agricultural tradition of Markham for years to come.
The Town of Markham has designated Adam Clendenen’s House under the Ontario Heritage Act.