The Big Dig was a massive construction project in Boston, aimed at improving the city's traffic flow. It involved burying a major highway, the Central Artery, underground to reduce congestion and create more public space. This project transformed the cityscape, allowing for parks and pedestrian areas to flourish above the new tunnels. Despite its benefits, the Big Dig faced many challenges, including budget overruns and construction delays. It became one of the most expensive highway projects in the United States, costing over $14 billion. However, it ultimately helped modernize Boston's infrastructure and made the city more accessible for residents and visitors alike.