Skylines are a prominent part of most cities. The natural landscapes surrounding cities make up their natural skylines, while the general shape formed by the silhouette of buildings and other urban features comprises their built skylines. This study sought to determine whether the natural skylines of cities affect residents’ preferences for the shape and height variation of built skylines. To answer this question, the authors selected three cities in Iran with different natural skylines (moun- tainous-desert, mountainous, and desert). Based on the Cochran formula, the authors selected a sample of 384 participants from each city. Next, they created nine images using different combina- tions of two variables representing the general shape of the skyline (concave, convex, or flat) and the variation in building height (low, medium, or high). The authors analyzed the collected data using SPSS 19 software. They examined the significance of differences in public preferences in the three cities with regard to variations in building height and the general shape of the skyline using inferential statistics (Kruskal-Wallis, Mann-Whitney U, and chi-square tests). The results showed that participants preferred a degree of building height variation that was consistent with the shape of the surrounding natural environment. However, in terms of the general shape of the skyline, participants preferred the opposite, favoring a general shape that contrasted with the natural environment. Respondents from the mountainous-desert city, Tehran, preferred a flat skyline due to the varied terrain of the natural environment. Similarly, respondents from Hamedan preferred a concave skyline, which contrasted with the shape of their mountainous natural skyline. Finally, respondents from the desert city, Yazd, preferred the contrast of the convex skyline.
