Through the tinted windows of the jeep, the barren landscape shimmered - and yet by local standards it was a mild day. On hot summer afternoons here in this eastern corner of Iran, temperatures can reach as much as 55C. My companions suggested I should be glad it was still only springtime. As we sped along the edge of the Pakistan-Iran border, I spied what I at first took to be a mirage. I was told, carrying contraband. Perhaps they'd slip across the border when it got dark.
Smuggling is a common trade here.
Iran has huge oil reserves, and fuel smuggled into Pakistan can fetch many times its local cost. Thanks to the lucrative market in Europe and the Middle East, it is a tempting trade - one that has made Iran one of the busiest drug transit routes in the world. Mindful of the drugs threat, the Iranian Government has sought to stop the flow of narcotics completely. It's here on the eastern borders with Afghanistan and Pakistan that their ambition has most obviously crystallised. Every few kilometres along the road, we passed small army outposts, which look uncannily like miniature medieval castles - complete with neat stone battlements.