While Hilo's coast is lined with reefs rather than sand, its gentle waters are ideal for stand up paddle surfing (SUP) – launch from Reeds Bay Beach Park or Mokuola (Coconut Island). For surfing, head to Honoliʻi Beach Park, but only if you're an experienced surfer.

Diving is best on the Kona side but there are decent shore-diving spots in or near Hilo; inquire at Nautilus Dive Center.