Key Facts

• NEOM is a massive project in Saudi Arabia costing about $9 trillion and includes plans for a linear city called The Line.
• California's high-speed rail aims to connect key areas and has faced budget increases from $33 billion to over $135 billion.
• King Abdullah Economic City in Saudi Arabia, costing around $100 billion, has developed a large port and a special economic zone.
• The Lower Thames Crossing in the UK is a large road tunnel project expected to open in 2032, costing roughly £10 billion ($13.3 billion).
• California's rail project construction is active on a 119-mile stretch, and future work is planned to extend to 171 miles.
• NEOM is part of Saudi Arabia's Vision 2030 to diversify its economy beyond oil reliance.
• King Abdullah Economic City was announced in 2005 and has seen numerous developments since, including industrial and logistics sectors.