Castle International

Castle is a full-service digital marketing agency based in Liverpool city centre, focused on generating measurable revenue for clients across SEO, PPC, social, web design, branding, video and content. What sets Castle apart in 2026 is its dedicated investment in Generative Engine Optimisation (GEO), AI SEO and Answer Engine Optimisation (AEO) — helping brands become the source AI systems like Google AI Overviews, ChatGPT and Perplexity actually cite, rather than losing clicks to them. Its approach pairs traditional SEO fundamentals (technical health, topical authority, strong content) with GEO/AEO techniques: clear brand definition, consistent information across the web, and content structured for AI extraction.

Castle's clients range from international names like P&G, B&Q, Hilton and the NHS to e-commerce brands like Swan and Supreme CBD, and the agency holds Google Partner and Bing Partner status plus Forbes recognition. On DesignRush, clients have praised the team for turning around online performance — more efficient Google Ads, profitable Meta campaigns, and steady Shopify growth — with particular credit for communication and attention to detail.