# Unraveling the hidden organisation of urban systems and their mobility flows

## TL;DR

This study analyzes the structural and functional organization of 10 megacities using human flow data and street networks, revealing complex patterns of segregation and integration that inform urban planning and policy.

## Contribution

It introduces a novel combined analysis of human mobility and street network data to quantify urban organization, highlighting the complex interplay between city structure and human flows.

## Key findings

- Large cities are more segregated and less integrated.
- Urban flow patterns resemble small-world networks.
- Heterogeneity in flows can enhance city integration.

## Abstract

Increasing evidence suggests that cities are complex systems, with structural and dynamical features responsible for a broad spectrum of emerging phenomena. Here we use a unique data set of human flows and couple it with information on the underlying street network to study, simultaneously, the structural and functional organisation of 10 world megacities. We quantify the efficiency of flow exchange between areas of a city in terms of integration and segregation using well defined measures. Results reveal unexpected complex patterns that shed new light on urban organisation. Large cities tend to be more segregated and less integrated, while their overall topological organisation resembles that of small world networks. At the same time, the heterogeneity of flows distribution might act as a catalyst for further integrating a city. Our analysis unravels how human behaviour influences, and is influenced by, the urban environment, suggesting quantitative indicators to control integration and segregation of human flows that can be used, among others, for restriction policies to adopt during emergencies and, as an interesting byproduct, allows us to characterise functional (dis)similarities of different metropolitan areas, countries, and cultures.