A rising tide can change the water level 9 feet on beaches in Northern California in only six hours! Some beaches in Humboldt County have access only during lower tides because of headlands that stick out into the surf during high tides. If you go for a walk on these beaches during low tide then you might find that your return route is cut off by the rising tide. Even if your return route is not cut off, the rising tide may force you to walk dangerously close to the surf to get around headlands. Use a tide book, or the link on this website, to plan your trips to beaches with headlands to make sure you can get back.