 Complete the following phrase:  Initially, public roads in the village were used for the race course. In 1956 a permanent circuit for the race was built. In 1968 the race was extended to six hours, becoming the 6 Hours of Watkins Glen. The circuits current layout has more or less been the same since 1971, although a chicane was installed at the uphill Esses in 1975 to slow cars through these corners, where there was a fatality during practice at the 