This project aims to protect the sonic cultural heritage of contemporary Istanbul in a digital archive. In this context, intangible cultural heritage is considered from an acoustic perspective, and this is in urgent need of protection. Since many sounds are important sonic symbols that indicate the cultural, social, political, and economic conditions of a specific urban area in a certain time period, it is crucial to collect and preserve these sonic cultural elements before they are lost. Sound is already a physically temporary phenomenon; cultural sounds, however, are twice endangered due to the fact that intangible culture is constantly changing and evolving. Based on an online survey and further research on everyday life practices in Istanbul, we have determined a number of characteristic sonic cultural heritage elements and started the one-year-long process of field-recording in January 2015. These field recordings will be archived and preserved in the Koc University Library Digital Collections, soon to be available for public usage. For easy access to accurate information, we have developed detailed metadata for the collection. It is hoped that this database will form the foundations for a longitudinal archive of the sonic heritage of Istanbul beyond the presently planned field recordings.