It contains the perforant path (the main input to the hippocampus, extending from the entorhinal cortex to dentate gyrus), along with several other fibers interconnecting the entorhinal cortex, parahippocampal gyrus, and associated areas.
This structure comprises the principal input to the hippocampus, namely the perforant path, which originates from the entorhinal cortex and terminates at the dentate gyrus. Furthermore, it includes fibers that connect the entorhinal cortex, parahippocampal gyrus, and surrounding brain areas.