## 1 Introduction  
The role of transport in sustainable development has been widely recognized since the 1992 United Nations Earth Summit and Agenda 21 document. Further, at the 2002 World Summit on Sustainable Development and at the 2012 United Nations Conference on Sustainable Development (Rio +20) transportation and mobility were considered central to sustainable development. Sustainable transport achieves better integration in the economy when it respects the environment; it improves social equity, health, the resilience of cities, urban-rural linkages and productivity of rural areas [1]. In the 2030 Agenda for Sustainable Development, sustainable transport is mainstreamed across several Sustainable Development Goals (SDGs) and targets. Specifically, target 11.2 is aimed at providing \"access to safe, affordable, accessible and sustainable transport systems for all, improving road safety, notably by expanding public transport, with special attention to the needs of those in vulnerable situations, women, children, persons with disabilities and older persons\" [2]. In this sense, studying transport social needs served by public transportation is an essential matter to evaluate target 11.2. In recent decades, the expansive urban development model of the Guadalajara Metropolitan Area (GMA) has increased individual motorized journeys. The kilometres travelled by private vehicle increased by more than 942% between 1980 and 2017 [3]. Despite this growing trend of private vehicle use, 34% of daily trips are made by public transport. In this context, the transport policy focused on the mass public transport system (MPTS), known as SITEUR, to increase multimodal choices, reduce air pollution and improve the quality of journeys [4]. SITEUR mainly serves the center of the metropolis. Specifically, it serves four of the nine municipalities with a multimodal system: light rail transit, bus rapid transit, and buses. A considerable proportion of people living in the suburbs travel on conventional buses operated by private carriers. Even though the fare is the same for SITEUR and conventional buses, the latter have poor regulation and make inefficient attempts to improve the quality of travel [3]. Besides the private carriers over the last mile to access the mass transport system and reduce transport related exclusion, other features, such as Park and Ride, are designed to support the successful operation of the system. Park and Ride are parking areas located in the vicinity of mass transport peripheral stations. People can leave their private vehicles there and use public transportation to travel to central areas. Unfortunately, the Park and Ride paradigm is not as well-established in the GMA, as it is in many cities. For instance, the Park and Ride system in Warsaw reduces social exclusion as cars, bikes and motorcycles can be parked in interchange nodes [5; 6]. Despite the fact that transport-related social exclusion has been studied in Latin American cities [7; 8], empirical and quantitative in-depth socio-spatial research is needed to identify whether transport systems include or exclude the people with transport disadvantages [9]. The analysis of the spatial and social contribution of SITEUR in the context of metropolitan mobility is relevant, given its quality service, contribution to multimodality and to the environmental quality of the city. This is even more pertinent, considering that the infrastructure of SITEUR has incurred great costs, a public debt that will be paid throughout future decades [10]. In this context, the aim of this research was to calculate the level of coverage of the provision of SITEUR with regard to the social needs of transport to find out whether SITEUR contributes to achieving 11.2 SDG target. In order to facilitate this, three indexes were conceived, calculated, and mapped with geographic information system and principal component analysis methodologies. First, an Index of Mass Transport Provision (IMTP) was measured through proximity, frequency, and capacity.