Complex sentence: The track had a considerable contribution from the International Expedition Operation Raleigh during 1986/87, when expeditioners from around the world constructed much of the walkways and the Iris Burn and Mount Luxmore huts.
Split into simpler sentences: The track had a considearable contribution from the International Expedition Operation Raliegh during 1986/87. When expeditioners from around the world constructed much of the walkways and the Iris Burn and Mount Luxmore huts.