The growing dependence on private cars has intensified the need to develop active-transportation infrastructure and to evaluate its traffic-related impacts simultaneously. This study proposes an integrated framework for prioritizing dedicated bicycle routes and assessing the operational effects of the preferred alternative in Kermanshah, Iran. Five candidate routes were evaluated using six criteria: hourly traffic volume, longitudinal gradient, roadway width, number of intersections, speed limit, and on-street parking conditions. Data were collected from 368 users and 15 transportation experts, and the questionnaire demonstrated satisfactory reliability, with a Cronbach’s alpha of 0.87. Criterion weights were determined using the Friedman test, the candidate routes were ranked through the Technique for Order Preference by Similarity to Ideal Solution (TOPSIS), consistency was examined using the Analytic Hierarchy Process (AHP), and network performance was assessed through AIMSUN microscopic traffic simulation. The Friedman test indicated a significant difference among the relative importance of the criteria (p < 0.001). Intersections and network nodes received the highest mean rank (11.58), followed by traffic volume (10.03), whereas on-street parking had the lowest mean rank (5.38). Route 2, Second Si-Metri Street, was identified as the preferred alternative, with a relative closeness coefficient of 0.671, while Route 1 ranked lowest, with a coefficient of 0.352. Under the scenario involving a 28% reduction in car trips, average traffic speed increased by 50%, while travel time, fuel consumption, total emissions, and traffic density decreased by approximately 39.7%, 29.9%, 26.6%, and 20.7%, respectively. The findings demonstrate that integrating multi-criteria decision-making with microscopic traffic simulation can improve route-selection transparency, quantify network-level benefits, and support evidence-based sustainable transportation planning.