Yes, there are metal detectors on the Eurostar. Security for the Eurostar is much more similar to airport security than it is to standard domestic train travel. Before boarding at stations like London St. Pancras, Paris Gare du Nord, or Brussels-Midi, every passenger must pass through a security checkpoint. This involves placing bags, coats, and belts through an X-ray machine while the passenger walks through a metal detector. In 2026, these checks are mandatory because the Eurostar travels through the Channel Tunnel, which is a high-security international border. However, the process is generally faster than at an airport because there are no restrictions on liquids; you can bring your own drinks and toiletries of any size through security. You will also go through a passport control check (Customs and Immigration) immediately after the security screening, as you are "clearing the border" before you even step onto the train.