Gamla Uppsala is a spectacular area filled with archeological remains dating back to the Iron Age. There have been several excavations in the area, the biggest one carried out between 2012 and 2013 with the construction of a tunnel that is a part of the railroad Ostkustbanan.An important tool in understanding the Iron Age civilization in Gamla Uppsala is to know what houses were used for. This is where a method called macrofossil analysis can be used with great success. By analyzing earth samples from postholes, graves, wells and hearths macrofossils like seeds and slag can be found and used to interpret a house based on the material.This study is going to use samples that were not prioritized during the excavations for the analysis in order to answer what function these houses had.The macrofossil analysis conducted during this study showed a lot of fresh seeds but also charred material that consisted mostly of grain seeds. An interpretation of the houses using the material found within the earth samples was made and the postholes was likely dwelling houses.Hopefully this study can contribute to a further understanding of Gamla Uppsala during the Iron Ages.