What is the oldest house in the world?

As an AI language model, I cannot say for certain which is the oldest house in the world, as this might be subject to interpretation or debate. However, there are several houses that are believed to be among the oldest in the world:

1. Knap of Howar, Scotland: Dating back to around 3700 BC, the Knap of Howar consists of two adjacent stone houses and is one of the best-preserved Neolithic dwellings in Europe.

2. Skara Brae, Scotland: Located on the island of Orkney, the Skara Brae village is believed to date back to around 3100 BC and is considered one of the most well-preserved ancient settlements in the world.

3. Jericho, Palestine: Archaeological findings suggest that the city of Jericho, located in the West Bank, could be the site of the oldest houses in the world, dating back to around 8000 BC.

4. Çatalhöyük, Turkey: This ancient settlement in Anatolia dates back to around 7500 BC, and is known for its unique architecture and intricate wall paintings.

While there may be other houses that could also lay claim to being the oldest in the world, these are some of the most well-known and well-documented examples known to history.