The trail is all climb going up 1.5 miles, there is a rest area up top, a Green painted covering with a picnic table. The way back is all downhill with a few very short low grade climbs. Epic trail, rocks of all sizes, roots, some pine needles, lush green jungle like scenery. Tight switchbacks, you will have to dismount quite a bit. Can get air in some places. Trail is on edge just about the whole way. Most of the trail is all shade by lush green trees. Tough, but fun and worth it.
From Honolulu Airport head East on I H-1. Keep right at the fork staying on I H-1 (Waikiki/Honolulu) and merge onto I H-1. Then stay on this highway, it turns into H-72. Look for Kuliouou Rd. and turn left towards the mountain, the road will bend left, then stay right onto this road as it turns through the neighborhood. Turn right on Kalaau Rd. The road ends at a culdesac, DO NOT park in the culdesac. Instead park along the road before it. Be sure not to block driveways (even across the street) or mailboxes and you'll be alright. Trailhead starts by the sign at the peak of the culdesac.
http://www.singletracks.com/item.php?c=1&i=9139