Definitely worth the trip. Hiking through the lava field provides very interesting scenery but it gets extremely hot so bring plenty of water and start early. Closed toe shoes are a must but hiking boots aren't 100% necessary. Keep left to the Kings Highway to get to the beach. Doing this again I would skip the lamp post and head straight to the beach. Getting in the water at the beach at the end of Kings Highway is very rocky so wear shoes you don't mind getting wet.