Searched for http://whc.unesco.org/pg_friendly_print.cfm?action=list&cid=171&id_threats=90&index=41&maxrows=20 
Note: This calendar view maps the number of captures of http://whc.unesco.org/pg_friendly_print.cfm?action=list&cid=171&id_threats=90&index=41&maxrows=20, not how many times the site was actually updated.
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