Long-distance running confined area. Early tracks were usually on flattened earth or were simply marked areas of grass. The style of running tracks became refined during the 20th century: the oval running tracks were standardised to 400 metres in distance and cinder tracks were replaced by synthetic all-weather running track of asphalt and rubber from the mid-1960s onwards. It was not until the 1912 Stockholm Olympics that the standard long-distance track events of 5000 metres and 10,000 metres were introduced. Long-distance road running competitions are mainly conducted on courses of paved or tarmac roads, although major events often finish on the track
All-weather running track today. In the mid-1960s Tartan tracks, surfaced with a product by 3M. The name "Tartan" is a trademark, but many have misused it as a genericized trademark. This process was the first to commercialize a polyurethane surface for running tracks, though originally conceived for horse racing. Many Tartan tracks were installed worldwide, including at many of the top Universities in the United States. Among that list was a Tartan track installed in the Estadio Olímpico Universitario, home of the 1968 Summer Olympics at Mexico City, which were the first global championships to use such a track. Olympic shot put champion