  The concept of city or urban resilience has emerged as one of the key
challenges for the next decades. As a consequence, institutions like the United
Nations or Rockefeller Foundation have embraced initiatives that increase or
improve it. These efforts translate into funded programs both for action on the
ground and to develop quantification of resilience, under the for of an index.
Ironically, on the academic side there is no clear consensus regarding how
resilience should be quantified, or what it exactly refers to in the urban
context. Here we attempt to link both extremes providing an example of how to
exploit large, publicly available, worldwide urban datasets, to produce
objective insight into one of the possible dimensions of urban resilience. We
do so via well-established methods in complexity science, such as percolation
theory --which has a long tradition at providing valuable information on the
vulnerability in complex systems. Our findings uncover large differences among
studied cities, both regarding their infrastructural fragility and the
imbalances in the distribution of critical services.
