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Canada
Practice Relating to Rule 8. Definition of Military Objectives
Section H. Areas of land
According to Canada’s LOAC Manual (1999), a “specific area of land may constitute a military objective”. 
Canada, The Law of Armed Conflict at the Operational and Tactical Level, Office of the Judge Advocate General, 1999, p. 4-1, § 8.
Canada’s LOAC Manual (2001) states in its chapter on targeting: “A specific area of land may constitute a military objective.” 
Canada, The Law of Armed Conflict at the Operational and Tactical Levels, Office of the Judge Advocate General, 13 August 2001, § 406.2.
At the CDDH, Canada stated:
A specific area of land may also be a military objective if, because of its location or other reasons specified in Article 47 [now Article 52 of the 1977 Additional Protocol I], its total or partial destruction, capture or neutralization, in the circumstances ruling at the time, offers a definite military advantage. 
Canada, Statement at the CDDH, Official Records, Vol. VI, CDDH/SR.41, 26 May 1977, p. 179.
Upon ratification of the 1977 Additional Protocol I, Canada stated:
It is the understanding of the Government of Canada in relation to Article 52 that: a. a specific area of land may be a military objective if, because of its location or other reasons specified in the Article as to what constitutes a military objective, its total or partial destruction, capture or neutralization in the circumstances governing at the time offers a definite military advantage. 
Canada, Statements of understanding made upon ratification of the 1977 Additional Protocol I, 20 November 1990, § 8(a).