The Hawaiian equivalent to Old Faithful—at least in regularity, if not temperature—is an impressive plume of seawater that jettisons anywhere from 10 to 50 or so feet into the air above the rocky shoreline (fenced for safety reasons). The spout comes from the force of ocean swells funneling waves through a lava tube, with the most spectacular displays in winter and other high-surf days. The whoosh of the spraying water is often followed by a load moaning sound, created by air being pushed through another nearby hole. There’s an ample parking lot (as well as restrooms) on the site, but if you spot tour buses, don’t try to compete with the crowds for a Spouting Horn photo. Instead, browse the vendors of arts, crafts, and jewelry (from $5 bangles to Niihau shell leis costing hundreds of dollars) under the tents along the bluff, or watch the wild chickens put on a show until the buses pull out 15 to 20 minutes later. Keep an eye out for whales in winter.