<p>Khajoo Bridge in Isfahan is one of these successful historical examples. Taking it as a sample, we have tried to identify reasons _&nbsp; with an aim to find proper applicable approach_ behind the preservation of liveliness in this bridge in past and present .To begin we first explained the meaning of city design and criteria of desirable city space according to Jan Gehl ( a famous Danish architect, sociologist, and urban design consultant). Then we searched, studied and analyzed related documents and observations for better understanding of functions and liveliness of Khajoo Bridge. our comprehensive researches showed that elements used in designing and building of the khajoo bridge have been in agreement with Jan Gehl&rsquo;s criteria of desirable place (protection, comfort, joy). Evaluation of functions and personality of Khajoo Bridge during different eras also revealed that, by employing humanity, culture and architecture, design of the Khajoo Bridge is most harmonious with the third criteria of Jan Gehl for a desirable place (joy). Taking this approach (joyous-entertaining-life giving) has contributed to the sustention of the Khajoo Bridge in many years.</p>