Mauna Loa has been quiet since 1984, but it's erupted 33 times in the last 150 years. The experts say that's it's inevitable that all of Mauna Loa will be covered once again in lava. That's 65% of the Big Island.
Prelude: another stupid houli-boy adventure
I lived in Hawaii during the late '80s & early '90s. My job, then, allowed my frequent visiting of all of the islands.
One job sent me to the big island for several days. From the start, I busted my but to free up some part of my final day there. I passionately wanted to see actual lava flowing out of Kiluea.
On that last day, with only 3 hours to spare, I jumped in my rental car and hauled-ass, off to find that lava. Without a second thought....like an idiot, I headed straight to the volcanoes summit. By the time I got there, it was dark(& damn cold). I was increasingly anxious to find that damned lava!
Coming around a turn, I spied far down through the jungle, the glimmering orange glow of what must, of course, be the lava. Hazaah!! I parked, & ran down some forest trail, in the pitch black of how night is on the summit.
It was not the glow of lava, as I had been so sure of. What I found was an ancient, fairly large & lengthy, lava tube. It had been strung with mercury-vapor lights for the tourists.
Although it took little more than ten minutes for me to reach 'the orange glow'; it was more than two hours of wandering the black jungle before I found my car again. It did give me time to think, though.
I remembered that I already knew that lava flows, except during full-blown volcanic erruptions, never surface at the actual crater. They always first reach the surface several miles distant, down the hill from, the volcanoe summit. In this case, I missed by more than 30 miles.
If it hadn't been for damn near freezing to death, I probably would have felt a bit embarrassed.
I was very happy to move to Hawaii. I was also very happy to move away.