"Researchers believe the Yellowstone volcano, the size of Rhode Island, erupts every 600,000 years. There are 200 hot springs and geysers in this region with molten lava bubbling below the surface." Original article here.
Oh frabjous day, callooh callay, somebody got it right!!! Although, once again, does "the size of Rhode Island" mean a lot to people from outside Rhode Island? I hardly ever measure things in Delawares, or try to tell people "oh, so and so is about the size of Wales" (although, if I wanted to, a like minded maniac with better programming skills has made it easier to measure things in Wales at Size of Wales, should you get the urge.)
ANYWAY, the caldera at Yellowstone Supervolcano is damn close to the size of Rhode Island. If that thing gets frisky, we are so DOOMED. " The major features of the caldera measure about 34 miles (55 km) by 45 miles (72 km),"*, and Rhode Island is 37(60 km) miles by 48 miles (77 km), so that seems more than fair to me.