Also known as Stoa Basileios, it was a small colonaded building in the northwest corner of the Agora in ancient Athens. A statue of Themis (Justice) stood in front of the building. The laws of the city were stored there. It was the headquarters of the King Archon who was in charge of religious affairs in the city.

Socrates hung around the Royal Stoa a lot and bothered everyone, including Euthyphro, in the dialogue recreated by Plato. This is also the building were Socrates came to be charged with impiety and corrupting the youth.