Urban settlements often deal with the massive transportation problems caused by mixed land-use development and improper travel services. This situation propels travel accessibility issues within urban centers. This research is intended to focus on the 3rd largest city of Pakistan’s Sindh province, i.e., Sukkur, where residents were found struggling to reach their desired destinations. The study area has naturally grown without planning guidelines, generating traffic congestion and haphazard land-use patterns. This research aims to measure accessibility within the city center using trip rate analysis and a GIS-based isochrone model (1-km radius). In total, 234 household trips were randomly considered according to Morgan’s sampling standards. The results revealed that scattered locations caused heavy traffic volumes without public transport facilities. The ratio of traveling by bike for shopping was recorded at 17.24%. Commuting by car; home-based, health, and shopping trips were ranked 1st (5.52%), 2nd (2.76%), and 3rd (1.38%), respectively. The isochrone-based maps were delineated to clarify the temporal accessibility features. Only three shopping activities were found to be accessible within 6 min. Most of the banks were found to be highly accessible. None of the health facilities were located within a 0–6 minute isochronal boundary. Two entertainment sites were accessible within 0–6 min. The residential neighborhoods were not close to the city center. Only three parks and six religious facilities were accessible within 6–12 min. The study findings clarified mixed land use activities accessed through multiple travel modes in the city center. Executing traffic management implications is a need of the time to induce sustainable transportation guidelines. Besides, the results may contribute to SDG 11.2, i.e., “affordable and sustainable transport systems” available for local commuters. The findings of this study are also relevant to evaluating the progress of some cities on SDG 11.2 regarding accessing feasible transportation services.