The process of urbanisation has dramatically changed the cultural reality of the late 20th-early 21st centuries. A number of academic claims that cities (not states) play the most important role in it today. This article analyses the opportunities of using city space as an open educational space, the conditions determining the pedagogic impact of the urban environment on its inhabitants are also discovered. The experience of implementing participatory educational projects in Nizhniy Tagil, an industrial city in the Urals, is presented. Two cycles of historical quests are described. Both were initiated by the pedagogic university in order to enhance the historical memory of the city dwellers. The commemorative cycle includes the quests dedicated to the events of the Russian Civil War and the Great Patriotic War, as well as political reprisals. The second cycle, the Addresses of Child Creativity, presents the supplementary education system in our country. The authors come to the conclusion that a modern city can be seen as an open educational space, comprising various educational content in terms of its scope and quality. The open educational city space is used more intensively in bigger cities, where there are more informational, organisational, financial and other resources. The experience of Nizhniy Tagil shows that it is possible to enhance the open educational space in medium-sized and smaller cities through participatory commemorative projects. Historical quests in the city are a good example of such projects. Various historical institutions take part in developing these projects. Apart from the educational results, these quests help to shape the city's identity and to found social partnerships between cultural and educational institutions. The inclusion of monuments and memorial plates on the buildings into the quest itinerary allows attracting the attention of the city-dwellers to the problem of the preservation of cultural legacy.