This paper attempts to identify and critically discuss how travel behaviour may be affected by any extreme system-level conditions of the transportation system in the cities. These disruptions refer to non-recurrent events and indicatively include hazardous events, and perturbations of the road network. To this end, the international literature on the changes in travel behaviour in the case where system-level disruption occur is collected and analysed. The analysis is conducted on the basis of the three pillars of travel behaviour, namely travel mode, route and departure time choices. The results show that most people tend to postpone their trip when extreme weather conditions occur, whereas in case of a public transportation disruption travellers are keen on altering their route choice. Finally, a clear mode shift towards cars has been observed due to the outbreak of COVID-19 pandemic.