The giant metal walls keeping London above water

A barrier is a type of fence or other obstacle that prevents movement or access. It can also be an abstract problem or condition that makes it difficult for someone to achieve something or for people to communicate.

The River Thames is a major waterway in southern England that flows through London and into the North Sea. It is the longest river entirely in England and is known for its historical, cultural, and economic significance to the United Kingdom.

The plural form of gate, referring to movable barriers used to close an opening in a fence or wall. It also describes the specific areas in an airport where passengers wait to board their airplanes.