The First International Opium Convention is signed at The Hague.

The First International Opium Convention is a former international treaty signed at The Hague in 1912. The conference were an international effort by states to regulate the trade of opium and suppress illicit opium consumption. It was followed in 1925 by the Second International Opium Convention signed in Geneva.

The Hague is the capital city of the South Holland province of the Netherlands. With a population of over half a million, it is the third-largest city in the Netherlands. Situated on the west coast facing the North Sea, The Hague is the country's administrative centre and its seat of government, and has been described as the country's de facto capital since the time of the Dutch Republic, while Amsterdam is the official capital of the Netherlands.