Three Chilean architects say they have come up with a way to restore Bolivia’s lamented access to the Pacific Ocean without angering Santiago – a 150km tunnel running underneath the Peru-Chile border and ending at an artificial island built with waste from the tunnel about half a mile offshore.

Landlocked Bolivia has been lamenting the loss of its Pacific Ocean coast since a war with Chile 130 years ago and the issue remains fiercely contested today. As well as blocking diplomatic relations between the two nations, it is hampering the development of Pacific markets for Bolivia’s natural gas and mineral wealth.