Herat is one of the most graceful cities in Afghanistan. Its traditions go back to the Persian empire, with its exquisite blue and green glass, and its thriving poetry scene.
Now Herat is struggling with a darker side: drug addiction at a higher rate than almost anywhere else in the country.
In a dusty ravine on the outskirts of the city, Ahmad, a scruffy 20-year-old, is striking a match to inhale heroin.
It's a simple act he repeats throughout his day — heating a dark slab of heroin paste smeared on a bit of foil so he can smoke it.