OICC Press Creative City Design 2717-4190 9 1 2026 03 31 Assessment of the Impacts of Built Environment Characteristics on Trip Generation Rates of Trans-regional Commercial Land Uses: A Case Study of Mashhad City 10.57647/ccd.2026.0901.02 EN Ramin Ahooee Department of Civil Engineering, SR.C., Islamic Azad University, Tehran, Iran https://orcid.org/0000-0001-5633-5449 Abbas Babazadeh School of Civil Engineering, College of Engineering, University of Tehran, Tehran, Iran Ali Naderan Department of Civil Engineering, SR.C., Islamic Azad University, Tehran, Iran https://orcid.org/0000-0001-5842-0188 Journal Article 2026 03 31 Aims: This study aims to investigate the influence of built environment characteristics and physical attributes on trip generation rates for trans-regional commercial land uses. The primary goal is to identify which urban design and spatial factors most significantly affect traffic attraction in a metropolitan context, specifically within Mashhad, Iran. Methodology: The research utilizes an extensive database of 6.8 million daily trips in Mashhad, focusing on 33 selected regional-scale commercial developments. Variables were categorized into physical attributes (e.g., land area, floor area) and built environment factors (e.g., road density, bus stop density, and shopping unit density). Data analysis was performed using descriptive statistics, correlation analysis to detect multicollinearity, and linear regression modeling to evaluate the relationships between independent variables and the average hourly trips generated. Finding: The results indicate that trip generation is significantly influenced by four key variables: bus stop density, business unit density in the area, business unit density along streets, and total land area. Notably, the density of business units within the area emerged as the most influential positive factor. Conversely, business unit density along streets showed an inverse (negative) relationship with trip generation rates, suggesting that increased street-level density may lead to a reduction in certain types of vehicular trip attraction. Conclusion: The study concludes that traditional trip estimation manuals, which often rely solely on physical building size, are insufficient for developing regions. Integrating built environment factors particularly public transport accessibility and local commercial density provides a more accurate forecast for traffic impact assessments. These findings offer urban planners and transportation engineers a localized framework for managing the traffic implications of large-scale commercial developments in metropolitan areas.