5. The Ashram, USA

With no outward sign of luxury you might expect from bikini boot camps favoured by the stars, The Ashram is tucked away in the foothills of the Santa Monica Mountains in California. Here the emphasis is on retreat rather than pampering and you are expected to work hard to produce results. No cushy deal here because there’s no Internet, no phones and no TV, and instead, lots of strenuous hikes in the scenic mountains and endless dance and gym classes and raw food meals.

theashram.com

Famous fans of The Ashram include Oprah Winfrey, Gwyneth Paltrow, Catherine Zeta Jones and Colin Farrell.