It was a little after 4 am when Peter Burke stepped out of his tent and onto the ice in the foothills of the Elburz mountain chain in Iran.
Even in the pre-dawn gloom, he was acutely aware of standing in the shadow of mighty Mount Damavand, which at 5,671 meters is the highest peak in Western Asia.
Somewhere out there in the darkness lay its snow-covered summit, and Peter faced a tough 1320 meter climb to reach it. The Wellington civil servant was a long way from home, and he knew he had a big day ahead.
"Your mind can play tricks on you with high altitude climbs," says Peter. "I was excited and nervous, and there's always a thought in your head, 'Am I going to make it'."