#7: Downtown Houston in Texas
Beneath the streets, another downtown carries on in air-conditioned comfort. Houston’s tunnel network stretches for more than six miles, links 95 city blocks, and sits roughly 20 feet below the sidewalks. Office workers use it for lunch, shopping, and everyday errands, particularly when outside conditions become uncomfortable. Above ground, high humidity interferes with the body’s ability to cool itself through evaporation, and direct sunlight can raise the apparent burden well beyond the thermometer reading.
