Walls represent a group of man-made habitats that can be colonized by a limited variety of plant taxa due to a presence of conditions that are very different than the natural ones. This research includes walls on 27 locations in Zagreb city centre, on which flora was listed or sampled in order to determine its structure, biogeographical features and ecological adaptations. A total of 183 taxa belonging to 59 families were recorded. The families with the largest number of taxa were Poaceae, Asteraceae, Lamiaceae, Cichoriaceae, Rosaceae and Brassicaceae. Considering position on the wall, 34 % of all taxa were recorded only in the cavities at ground levels of the walls, while 20 % were found growing only from vertical surfaces. The most common life forms were hemicryptophytes (40,44 %), therophytes (28,96 %) and phanerophytes (24,04 %), and the prevailing floral element was euroasian (33,88 %), followed by neophytes, adventive taxa and cultivars (23,5 %). Cultivated flora makes up 15,3 % of all recorded taxa, while invasive species are present with 8,8 % of all taxa. Most of the recorded taxa are adapted to moderate temperatures, and considering continentality, the biggest part of flora belongs to the suboceanic-subcontinental type. Heliophytes and semi-skiophytes prevail among the taxa, as well as taxa adapted to moderately moist habitats, slightly acidic to neutral soils and soils moderately rich and rich in nutrients. The most present pollination agents are insects (64 %), and zoochory (58 %) is the most common type of seed dispersal. Average CRS values of all the locations indicate the predominant combination of competitive and ruderal strategy among the studied flora.