Marie and Nil had been enjoying their first days in Greece when a family emergency cut Marie's stay short. She has returned to France and it is unclear when she will return to the trip.

Fortunately, Nil has not been left to continue alone. Mateo, a brand manager for one of their primary sponsors (Zpacks), flew over from his home in the US to join him. Mateo is the 23rd guest to join the project.

Not content to just hike across Greece, Nil and Mateo decided they would target the country's highest point. Mount Olympus, the legendary home of the Gods, rises to nearly 10,000ft and is no small undertaking. To reach the mountain they trekked through picturesque Greek villages such as Pyrgetos, Kallipefki and Karya before starting their climb in late August. The weather was not ideal, with low clouds and poor visibility, but the pair felt that the conditions only added to the atmosphere and mystique of the place.