The 54-key property is owned by the Cadogan Family Estate, which bought it for £15.4 million in 2011. It closed for refurbishment in 2014.
Belmond says the property's interior design, by GA Design International, draws inspiration from the hotel's original features and rich history and heritage - from Sir Hans Sloane, to Kings of England, artists and writers and the scandalous stories of Oscar Wilde and Lillie Langtry.
"When you walk into a Belmond property you can feel the 'soul' of the place, and it's our job to keep the soul and spirit alive with the design concepts. We are working with talented designers to carefully merge the genuine elements of the local culture with a modern-day relevance that resonates with our guest's lifestyle and aspirations," said Belmond art and design director Joe Ferry.