Few rivers move so much earth as the Yellow, and here, at its mouth in Shandong, you can watch the land being made. The Huang He carries more silt than any other major river, a load picked up from the loess plateau, and where it slows at the sea, it drops it, building a delta that grows by many square kilometres in some years. The river has often changed course here. It has flooded, shifted and found new channels, and its mouth has moved hundreds of kilometres over the centuries, which is why the Chinese call it China's Sorrow.
The result is a flat, wet, shining country of mudflats, tidal creeks, reed beds and salt marsh, in the area near Dongying. The wetlands here are among the largest young wetlands in the world, and they are a vital stopover on the East Asian-Australasian Flyway, the route that carries millions of migratory birds each year between Siberia, China and Australia. In spring and autumn the flats fill with sandpipers, plovers, geese and cranes, and rare species such as the oriental stork and the red-crowned crane use the reeds for nesting and wintering. Tens of thousands of birds in the air at once is a sound as well as a sight.
The delta is also an oil field. The Shengli field, one of the biggest in China, pumps from beneath the marsh, and its nodding donkeys, pipelines and roads share the landscape with the reeds. The two worlds are oddly interleaved, with pumpjacks beside bird hides, and the flat horizon is broken by gas flares and wind turbines.
Riding on the delta means long, flat, straight roads, with wide skies and strong winds off the sea. The surfaces are generally good on main roads and poor on the farm tracks, and trucks serving the oil field share the road. Visitors who want to ride in China should check the rules on licences and permits well ahead, since they are strict. Fuel is easy to find in Dongying, the nearest city, and the reserve has few facilities, so bring water. Autumn is the best season for birds, and the sunrise over the flats is a good reason to stay overnight.