3 position signals introduced from Westgarth to Alphington Sep.1964 3 position signals introduced (and line duplicated) from Alphington to Ivanhoe, Dec. 1951 3 position signals introduced (and line duplicated) from Ivanhoe to Heidleberg, June 1949 3 position signals introduced from Heidleberg to Macleod Dec. 1958 Line duplicated from Rosanna Junction to Macleod Dec. 1958