What is the setting of Stormbreaker by Anthony Horowitz?

The novel is set in England, the country in which the author also resides. The novel begins in London, the large city where Ian and Alex Rider make their home. In time, the novel's setting switches to Port Tallon, Chelsea, where the Sayle Enterprises plant is located. In this location the main character lives in a large compound where the company has its plant and the owner has his home. Later, the main character explores the empty mines under the town where Sayle also has a secret lab.