Where is the headquarters of the European Commission located?

The headquarters of the European Commission is located in Brussels, Belgium. This city is not only the administrative center of the European Union but also serves as the de facto capital of the EU, housing major institutions such as the European Parliament and the Council of the European Union, alongside the Commission itself.

Brussels' significance stems from its role as a hub of international diplomacy and governance, where decisions that affect member states are made. The European Commission, which is responsible for proposing legislation, implementing decisions, and upholding EU treaties, plays a crucial role in the functioning of the EU. Locating such a key institution in Brussels allows for centralization and accessibility for the member states and other stakeholders involved in EU matters.

Other cities, such as Paris, Berlin, and Amsterdam, while important within their own contexts, do not serve the same administrative purpose within the framework of the European Union as Brussels does. Consequently, it is clear that Brussels is the correct answer due to its established role and function in European governance.