Valmiki Ramayana Yuddha Kanda Sarga 126 Shloka 16

विशालाक्षि broad eyed, एषः here, सागरे on the ocean, सलिलार्णवे salt ocean, मया by me, बद्धः bridge, सुदुष्करः very difficult, नलसेतुः built by Nala (called Nalasethu as it was built by Nala)

"Broad eyed lady! Here is the bridge built on the salty ocean by Nala, which was difficult to construct."