Arsenal’s London Colney complex is sometimes referred to as the “training ground that Nicolas Anelka built.” When the surly French forward left the Gunners for Real Madrid in 1999, the club reinvested his £22 million transfer fee in a much-needed training facility. They even had a chunk left over to spend on Anelka’s replacement—a struggling winger at Juventus by the name of Thierry Henry. It’s safe to say the Anelka sale panned out rather well for Arsene Wenger.



However, that was almost 20 years ago. Arsenal set the standard for the modern training ground, but in the intervening years Europe’s other elite clubs have steadily caught up—many of them having paid visits to Colney for inspiration.



That’s why, in March 2015, the Gunners unveiled plans for extensive building works at their Hertfordshire base, including the construction of a new player performance center. And when it finally opened last summer, it...