Silicon Fen
Silicon Fen is the working name of the technology cluster in and around Cambridge: a concentration of software, electronics and biotechnology companies that grew out of the University and its Colleges. It is a nickname, not an administrative area, and it has no official boundary.
In practice
The scale is tracked by Cambridge Ahead through an annual census of company accounts. In September 2026 its dashboard showed 25,872 companies with a combined turnover of £53 billion and 220,951 employees, including 26 companies valued above $1 billion. The datasets behind these figures cover firms within a 20-mile radius of the city centre, separating Cambridge-based firms from firms merely active in the area.
Why it matters to newcomers
Silicon Fen is probably why you are here: it is the job market, the client base and the dinner-party topic. Quoting the Cambridge Ahead figures, with the date you read them, beats repeating "Europe's Silicon Valley" clichés, and knowing the name signals you understand the city is a workplace, not just a university. Our full guide breaks the cluster into sectors, parks, spin-outs and investors.
Related
- Cambridge Phenomenon - the name for how the cluster started
- Spin-out - how University research becomes companies
- Silicon Fen: Cambridge tech cluster guide
Sources: Cambridge Cluster Insights.