Memorial plaques are periodically added to Kings Park's special Honour Avenues during dedication ceremonies held throughout the year.

Kings Park and Botanic Garden has more memorials, statues and honour avenues than any other park in Australia.

The planting of trees as a dedication to individual Service personnel who gave their lives while serving their country in a time of war seems to be an Australian innovation. This unique practice originated in Ballarat, Victoria when in 1917 Mrs Tilly Thompson proposed to raise funds to plant an 'avenue of trees' to honour the local men who had been killed in World War I.

The idea was taken up in Kings Park by Mr Arthur Lovekin, an original member of the Kings Park Board. May Drive became the first Honour Avenue in Kings Park and Botanic Garden in 1919. Relatives and friends of men and women who died during World War I (1914-1918) planted 400 oak and plane trees during a planting ceremony.

After World War II (1939-1945), 300 sugar gums (Eucalyptus cladocalyx) were dedicated on Lovekin Drive and honour the fallen of both World War I and World War II. The most recent addition to the Honour Avenues is Marri Walk; a roadway adjacent to May Drive. Marri Walk was dedicated on 18 April 1999 and honours the fallen of World War I, World War II and other engagements.

At the base of each tree along these avenues, is a plaque inscribed with the name of the deceased, age, date and manner of death and who dedicated the plaque. Members of the Highgate Returned and Services League have maintained the plaques in a voluntary capacity through the Honour Avenues Group since 1922. There are currently over 1400 memorial plaques along the Honour Avenues in Kings Park.