In a conjuncture of Brazil’s growing economy and increasing presence at the world stage, private companies in collaboration with the local government started a billion-dollar renovation of Rio de Janeiro’s port area, aiming at reviving an allegedly decadent and deserted district. According to the proposal published by the public-private partnership, the re-urbanization of the conveniently-located area could foster the development of real estate enterprises and leisure sites for a city ahead of the 2014 World Cup and 2016 Olympic Games. The novelty of the operation, however, would soon contrast with the uncovering of an old slave wharf and adjacent structures, which were part of a global slave trade hub between the second half of the eighteenth century and the first half of the nineteenth century. While the Valongo Wharf complex has since then become a significant site for Black activists, scholars and locals, having gained global notoriety with its classification as a World Heritage Site by the UNESCO in 2017, efforts toward its memorialization have not only been overshadowed by the neighboring private-sponsored enterprise, but also by the broader, long-lasting and often denied structural racism that permeates different levels of Brazilian society. This thesis examines the significance of the Valongo complex in the context of Brazil’s racial history and I argue that ruins have served as an incentive for the re-reading of history from the perspective of marginalized Black populations as well as a stage for current-day social activism against social and racial inequality, serving as an alternative archive that articulates grassroots organizations which memorialize the site. By doing it so, I also examine the diasporic contours of the Valongo case, which allow not only a transnational analysis on Black solidarity, but also the examination of the local tensions between the State and Afro-Brazilians. Methods-wise, this work includes ethnographic research descriptive of subaltern voices which attempt to affirm and preserve the site’s history, while promoting the alternative repositories of history that support their claims. As examined on this thesis, the ruins of the Valongo not only constitute a historical site but also stimulate the acknowledgement of centuries of struggles of Afro-populations, which have been subjected to enslavement and, after abolition, lack of access to services, housing, among other fundamental rights, being to this date targeted by institutionalized racism, often denied and neglected by discourses of colorblindness. As a site of history and memory, the Valongo is one of the many pieces of the African Diaspora, contributing to a transnational global diasporic imaginary that seeks to challenge Eurocentric discourses and histories, while centering the agency of Afro-Brazilians and Afro-Latin Americans in the formation of present-day societies, in spite the challenges arising from their structural and historical marginalization.