 Charles was born in Rideau Hall in Ottawa when it was the property of his grandfather, Thomas McKay, before it became the official residence of the Governor General of Canada.Although not formally educated, Keefer spent his early years employed as a surveyor on some of Canada's most important railway works including the Canada Central Railway (Ottawa to Carleton Place), the Chaudière branch of the St. Lawrence and Ottawa Railway, the Canadian Pacific Railway (Yellowhead Pass), and the Canada Atlantic Railway.Between 1872 and 1875, he worked on the construction of the Ottawa Water Works as assistant engineer.