The battle is between Anna and Joel, both masters of their own element, confronting each other over the latter's right to cross Anna's beach. 

The scene is a simple shore-line with a soft incoming tide in the waning hours of a long summer's day. The sand is wet and solid underfoot until one reaches softer dry sand and scrub, before the beach finally gives way to forest. As the contest is over Joel's decision to walk across Anna's beach, either side retreating from the beach-front admits defeat. Therefore, fleeing to deep sea or the forested region is forfeit for either character, as death is unlikely on either side. 

[img]https://adifferentstep.files.wordpress.com/2012/06/empty-beach-northern-oahu1.jpg[/img]