Further down the Hana Highway, around a half-mile past mile marker 22, you'll find Pua'a Ka'a State Wayside Park (that's always fun to say). Here you'll find a paved trail to several small falls and a picnic area. A larger falls can also be accessed upstream via a dirt trail. If you decide to go, use caution crossing the viaduct and be prepared for mud.Mongooses (yes that's plural) also hang out at the park. You may have already seen them streaking across the road. Some bright soul imported them to kill the rats that the sailors brought here on their boats. Well, they killed the ground rats and most of the ground birds but left the tree rats. They are now found on every island except Kaua'i.The little creatures run around this area gathering food left over from picnics. You are also likely to see the wild Jungle Foul (chickens) that frequent the area (that is, if the mongooses haven't gotten to them yet).
The large paved parking lot at this stop will be makai. Rest rooms are available here as well.UpdateSeveral renovations have been going on at Pua'a Ka'a State Wayside Park. This should include upgraded facilities.

Visitor Travel Guide