the Grand Shrines of Ise
Refers specifically to the Ise Grand Shrine complex (伊勢神宮), a major Shinto shrine in Mie Prefecture. The term 大廟 is a formal, somewhat literary designation.
The Grand Shrines of Ise are officially called Ise Jingū.
The common, standard name for the shrine complex. 伊勢大廟 is a more formal, less frequently used alternative.
伊勢 (Ise, the region) + 大廟 (grand mausoleum/shrine). 大廟 is a Chinese-derived term for a grand ancestral shrine, applied here to the Ise Shrines.