This book constitutes the refereed proceedings of the 4th International Conference on Research and Education in Urban History in the Age of Digital Libraries, UHDL 2025, held in Vienna, Austria, during November 3–5, 2025. The 13 full papers included in this volume were carefully reviewed and selected from 38 submissions.They are organized into the following topical sections: Theory, Methods, and Systematization; Data Handling and Data Schemes; Machine Learning and Technologies; Applications; Education; and BIM.