Today on the Panel, Wallace and panellists Sally Wenley and Raybon Kan discuss the lava caves that sit beneath Tamaki Makaurau.
Plus, they discuss the upcoming school census, and whether Rugby Union is having an "existential crisis".
Cross-section showing lava cave formation: Most lava caves form inside lava flows. The outside of the flow cools and solidifies, forming a crust of basalt around an internal tube filled with flowing hot lava. When the supply of lava stops, the molten liquid drains out leaving an empty tube or cave. ILLUSTRATIONS: GEOFF COX. Photo:
