1.2 million visitors experienced Utrecht's 'Fish Doorbell' in its first month, an underwater camera and digital doorbell system that alerts a lockkeeper to open a dam for fish.

In Utrecht, the Netherlands, a 'Fish Doorbell' has become a global sensation, with over 1.2 million visitors in its first month. The underwater camera and digital doorbell system allows people to alert a lockkeeper to open a dam, enabling fish to reach their spawning grounds. The Fish Doorbell gained popularity after videos on TikTok and international media coverage.