Rancagua
It is the capital of the Cachapoal Province and of the O'Higgins Region , located south of the national capital of Santiago . 
<triplet> Cachapoal Province <subj> O'Higgins Region <obj> located in the administrative territorial entity <triplet> O'Higgins Region <subj> Cachapoal Province <obj> contains administrative territorial entity <triplet> Santiago <subj> national capital <obj> instance of