The farther we travelled, the more nauseous it became. Soon we were swimming in pools of light Nigerian crude, the best-quality oil in the world. One of the many hundreds of 40-year-old pipelines that crisscross the Niger delta had corroded and spewed oil for several months.

Forest and farmland were now covered in a sheen of greasy oil. Drinking wells were polluted and people were distraught. No one knew how much oil had leaked.

The Guardian’s environmental editor reports on Nigeria. Hat tip to @Dollabrand.