The CDG Express, a high-speed train line designed to connect Paris with Charles-de-Gaulle Airport, has not yet transported a single passenger, even though construction began several years ago. Originally intended as a flagship project for the Paris Olympics, the train was meant to highlight the modernization of the Île-de-France regional rail network. However, the line remains unused, with no trains having operated from its starting point. The project, initially planned for completion in time for the 2024 Olympics, has been postponed to March 28, 2027, due to legal disputes that delayed construction. The budget has risen from 2.1 billion euros to 2.6 billion euros, funded through a government loan and shareholder contributions, without direct support from public funds. The operator, Hello Paris, has pledged to run the line for 15 years, aiming to attract over 9 million passengers annually at a fare of approximately 25 euros per trip. This would ensure the project’s profitability. However, years of delays have led to additional financial costs, including 30.21 million euros in compensation for the operator and adjustments for inflation. The contract with Hello Paris also includes a financial commitment of 200 million euros per year for operations, underscoring the project's economic significance. Technically, the CDG Express remains an appealing project. It would provide a direct 32-kilometer link between the Est station in Paris and Terminal 2 of Charles-de-Gaulle Airport, covering the distance in just 20 minutes. Trains would run every 15 minutes, seven days a week, from 5 a.m. to midnight, offering a fast and frequent service. Despite these advantages, the project has faced multiple hurdles, including legal challenges, the impact of the health crisis, and shifting political priorities, all of which have contributed to delays and rising costs. The primary objective of the CDG Express is to ease pressure on the RER B, a heavily used regional rail line that is struggling with increasing passenger numbers. However, the project’s success ultimately depends on its ability to attract enough travelers to justify the investment. Public skepticism has grown due to years of delays, raising questions about whether the line will meet its projected usage and financial goals.