The origin the name of this part of the arboretum goes back to before the mid 1920s.
About 1927 the roads were metalled for the first time and winter access was available. Prior to this in the deep mud of winter, the only way to transport goods up to Rere and beyond to Wharekopae was with bullock teams. Douglas Cook let them camp in this area and his description of the noise, singing, drinking, cooking, animals etc was to call the whole thing a CIRCUS.
Earlier shelter belt pines were felled in 1949 and seedling regrowth followed so that in 1956 when Douglas Cook planted the Circus in imported plant material, the Circus Ridge was a dark background. At that time the Kahurangi stream was also dammed and four ponds were formed.