Sunset at Olympic Stadium

It's sunset at Phnom Penh's Olympic Stadium. Across the top ring of concrete seating hundreds of Cambodians –

mostly women over 55 – are doing the mashed potato in front of several sound systems. Next is a  gangnam-style move.  Beside the throng, sugar-cane juice stalls and makeshift beer stands sell refreshments. Here, open-air aerobic dance classes happen at dawn and dusk every day. Down by the pool there are yoga classes, kids are jumping off the diving boards and on the field local teams are playing soccer. But I'm not here to watch sport and recreation, I'm busy admiring the architecture. In the undercover area where a volleyball game is taking place, we walk in the extreme humidity to the very top. Our guide, a final-year architecture student, Virak Roeun, asks us to take a seat.