Various aspects of comfort are analysed through a set of questions asked of 90 urban pedestrians. Answers show the contribution that clothes, time adaptation and other non thermal effects make in lowering the skin wetness and the perception of warmth. A shift exists between theory (established with subjects in climatic chambers) and statements. Searching for a comfortable feeling in this city, the hottest in France (metropolis), but without any river, lake or seaside, results from water evaporation at the clothing level for the immediate body environment, and also for the outside air cooling. The enormous need of water for a natural air conditioning was one reason for the aqueduct built by the Romans. (C) 2001 Elsevier Science B.V. All rights reserved.