<P> By the late 1960s, many of the candy - striped Golden Arches stores had been modified with enclosed walk - up order areas and limited indoor seating . In June 1969, McDonald's introduced a new "mansard roof" building design featuring indoor seating . The natural brick and cedar shake look mansards were a response to critics who berated McDonald's architecture as too garish . It became the standard for McDonald's restaurants, and franchise holders were ultimately required to demolish older restaurants and replace them with the new design . The first McDonald's restaurant using the "mansard roof" design opened that same year in the Chicago suburb of Matteson . </P> <P> McDonald's spectacular growth continued in the 1970s . Americans were more on - the - go than ever, and fast service was a priority . In 1972, the company passed $1 billion in annual sales . By 1976, McDonald's had served 20 billion hamburgers, and system wide sales exceeded $3 billion . </P> <P> The company pioneered breakfast fast food with the introduction of the Egg McMuffin in 1972 when market research indicated that a quick breakfast would be welcomed by consumers . Five years later McDonald's added a full breakfast line to the menu, and by 1987 one - fourth of all breakfasts eaten out in the United States came from McDonald's restaurants . In test market locations, such as New York City, McDonald's added a full breakfast line to its menus in 1975 . </P> <P> Kroc was a firm believer in giving "something back into the community where you do business". In 1974 McDonald's acted upon that philosophy in an original way by opening the first Ronald McDonald House, in Philadelphia, to provide a "home away from home" for the families of children in nearby hospitals . Twelve years after this first house opened, 100 similar Ronald McDonald Houses were in operation across the United States . </P>

When did mcdonald's first start serving breakfast