Museum documentation is usually understood as a systematic way of obtaining, creating and organising information and knowledge about objects and collections. However, this traditional perception of museum documentation may not provide the appropriate means to collect information and knowledge regarding everyday life and its cultural heritage, such as archaeological monuments in cityscapes. By being ‘exposed’ to daily life, archaeological monuments acquire dynamic, personal and everyday meanings, often too familiar and ephemeral to be grasped. To what extent can, then, museums access and document this everyday knowledge that shows the way people understand monuments in their daily life? Using as a context archaeological monuments in the city of Thessaloniki (Greece), this paper suggests that documenting ‘everyday meanings’ cannot be interpreted as the making of a complete record of them. It should be, rather, approached as the development of a ‘mobile gateway’, through which everyday knowledge can enter museums. The paper goes on to explore the potential of mobile phones, used by their owners, to capture and communicate everyday meanings of archaeological monuments. Mobile phones are considered ‘everyday technology’ and they are, already, used in disseminating museum knowledge to users. Drawing on fieldwork and qualitative investigation in Greece, the paper suggests that mobile phones could, also, be used as a means for museums to access and reveal everyday knowledge. In this case, museum documentation is seen not as an exhaustive systematisation of everyday knowledge, but an open communication channel, a ‘mobile gateway’, between people and museums through the use of mobile technology in everyday life. ‘No one, wise Kublai, knows better than you that the city must never be confused with the words that describe it. And yet between the one and the other there is a connection’. Italo Calvino (1997:61)