Tápiószecső is a village in Pest county, Hungary. It is a very old settlement which has been inhabited since prehistoric times. Evidence of human activities has been found and exhibited in the Hungarian National Museum. In the Middle Ages the town was also known as 'Key-Town' which referred to the key of the city walls. According to tradition, the guardian of the key was called 'Szecső'. It is commonly believed that the name of the town origins from this guardian.