Naulu Trail has only one trailhead, so you're looking at an in and out hike. The total elevation difference for Naulu Trail is 632 feet which is a lower than average number. Even though this is not a very long wilderness hiking trail it's always great to bring some emergency supplies, you never know what could happen. Being 4.2 miles long it's an average length trail. This backcountry trek shouldn't take more than 3.5 hours, but of course some people walk a bit slower and some a bit faster. The trail stays roughly within the same elevation zone the whole time, so you get pretty much the same conditions along the whole trail.