Cathedral Grove in the MacMillan Provincial Park is located east of the community of Port Alberni, BC on Vancouver Island, Canada. The 157 hectare wilderness park was created to protect the old growth forests within the Coastal Douglas Fir Biogeoclimatic Zone. Travel towards the community of Parksville and Qualicum Beach on Vancouver Island in BC, Canada. From the Island Highway look for the Hwy #4 exit. Continueing driving Hwy #4 towards Port Alberni. Cathedral Grove located in MacMillan Provincial Park is located 15 kilometres east of Port Alberni. Cathedral Grove Provincial Park on Vancouver Island provides visitors a great opportunity to view the inner workings of a westcoast rainforest. Throughout the park are a series of short hiking trails with information signs, sitting benches and viewing platforms. handicap accessible.