Puri Lighthouse stands near the beach, giving the pilgrimage city a coastal landmark as well as a religious one. From the tower, when access is available, the view takes in the Bay of Bengal, the long strand of Puri beach, and the dense town behind it.
It is a simple sight, but a useful counterpoint to the temple-focused side of Puri. Go for the views and the sea air, and combine it with a beach walk rather than treating it as a long standalone visit.