We stopped at Kaumana Cave on the way in to Hilo.
Bring a flashlight--you can go exploring back there for hours! Alas, we did not.
Hilo is a funky, somewhat déclassé tropical town on Hawaii's east coast. Annual rainfall here is 100"! That's 26" more inches than I am tall! I can hardly comprehend that. Hiloans have to ration water in years when rainfall is less than 70". Hilo was devastated by a tsunami in 1946.
Strawberry papaya with lemon is your favorite breakfast in Hawaii. (These are not strawberry papayas, but they look similar.)
What did people do here before the arrival of lemons?
If you want more substantial fare in Hilo, I guess I would recommend Cafe Pesto. We ate at the Cafe Pesto on the island's west coast last night and it was very good.