Saudi Arabia's futuristic megaproject Neom has come to a standstill, as the extraordinary costs of the planned city have collided with financial reality. After sinking more than $50 billion into Saudi Crown Prince Mohammed bin Salman's dreams of a sci-fi metropolis, the kingdom is now spending billions of dollars more to wind down contracts, leaving mammoth-sized partially built structures to gather sand in the desert. WSJ's Eliot Brown analyzes internal documents and satellite images to show how and why the world's largest construction project came to a halt, and what comes next for Neom. Why the World's Largest Megaproject Collapsed...