Sanwo-Olu referred to Lagos as the “fifth or sixth largest economy”. He however didn't say whether he meant in Nigeria, Africa or the world.

His office has also yet to respond to Africa Check's request to clarify the claims in this report. However, similar claims have been made in the past comparing Lagos’ gross domestic product (GDP) with that of African countries.

On the campaign trail in October 2022 president Bola Tinubu, a former governor of the state, said Lagos was the fifth largest economy in Africa, and two months before that his deputy, Kashim Shettima, said the city was the third largest economy on the continent.

GDP is a commonly used measure of the size of a country's economy. It is the market value of all the goods and services produced in a given period, usually a year.

GDP is the most common way of measuring an economy, Gafar Ijaiya, a professor of economics at the University of Ilorin in north-central Nigeria, told Africa Check.

He said it was possible to compare a sub-national entity like Lagos to a country, simply on the basis of GDP size. He explained that the sheer concentration of many economic activities in Lagos made it comparable to some countries, noting that the state was an import and export gateway for Nigeria, Africa's largest economy.

The state was also a major transport hub, Ijaiya said. “There is a lot of federal presence in Lagos, being a former federal capital,” he added.

At least 10 countries had a higher GDP, not five or six

In June 2022, the Lagos ministry of economic planning and budget put the state’s GDP at N26.587-trillion in 2021. This remains the most recent data on the state’s official website.

This was equivalent to US$69.78-billion at that year’s official exchange rate, of N381 to the dollar.

But there were at least 10 African countries with a GDP of over $70-billion in 2021, according to the World Bank.

Lagos’s contribution to the national GDP in 2021 was 14.7%. In that year, the World Bank put Nigeria’s GDP at $440.84-billion, rising to $472.6-billion in 2022.

Explaining the enormity of his task, the governor said Lagos was the largest city-state in Nigeria. He didn't specify whether he meant landmass or population, nor did he define a city-state. So we asked two experts about this.

Calling Lagos a city-state means that all the geographical regions of the state are considered part of the city. By this definition, Lagos is the only city-state in Nigeria, Felix Ilesanmi, a professor of urban and regional planning at the Modibbo Adama University of Technology in Yola, northeast Nigeria told Africa Check.

“Abuja would have been the other city-state if one considers Abuja as the country’s 37th state. [On the other hand] Kano is a large city constituting a large portion of the state. However, there are some parts of Kano state that are outside Kano city,” Ilesanmi said.

“Lagos is about the most organised city in Nigeria. It fits the various definitions of a city, such as having a significant population and infrastructure, and it is also a state,” said Mustapha Zubairu, a professor of urban and regional planning at the Federal University of Technology in Minna in the centre of the country.

“Kano is much larger than Lagos. It is almost a city-state. However, some of Kano’s 44 local government areas are not within the metropolis known as the city of Kano,” Zubairu told Africa Check.

According to the experts, Lagos is the only city-state in Nigeria and therefore there is no basis for comparison.

London-based Time Out is a media and entertainment company, known for its lists and rankings of things to do in cities across the world.

Sanwo-Olu told the journalists that Time Out ranked Lagos as the 18th most “preferred city to stay in the world”. (Note: The publication placed Lagos 19th on its “50 best cities in the world in 2024” list.)

Celebrating the achievement, the state government said the ranking had placed the city of Lagos ahead of “Melbourne, Naples, Singapore, Miami, Dubai, Beijing, and Montreal, among others”.

Sanwo-Olu said the ranking came because his administration was doing the “difficult and unpopular” things to improve the city.

We asked Time Out if that was their finding.

“Our Best Cities lists are not meant to be a measurement of the work of governments,” the publication’s chief communications officer, Alexandra Rieck, said.

‘We are not looking into the work of an administration’

Instead, the publication focused on helping people “to experience the best of the city based on editorial curation by local expert journalists, editors and writers who know their cities really well,” said Rieck.

“As such, we are not looking into general metrics of standard of living or the work of an administration or government. What our ranking is instead about are culinary and cultural experiences in cities and what they offer in terms of the best things to eat, drink, see and do, so it’s attributable to the efforts of local talents, people and businesses, and these should be celebrated,’’ she said.

So the survey does not claim what Sanwo-Olu and his administration said it does.

Other rankings have offered a different take. An example is the annual Economic Intelligence Unit (EIU) global liveability ranking, which consistently ranked Lagos in the bottom five.

Lagos was ranked 139 out of 140 cities in 2021, 171 out of 172 cities in 2022 and 170 out of 173 cities in 2023.

The EIU liveability ranking measures cities based on 30 qualitative and quantitative factors in five broad categories: stability, healthcare, culture and environment, education and infrastructure.

Urban experts have also written about the stark challenges of governing Lagos.

Asked about the incessant flooding in Lagos, Sanwo-Olu said there wasn’t much his government could do proactively because of natural factors such as the amount of rain the city gets and climate change.

He then said: “We are below the sea level and this is nature that we cannot do anything about.”

Lagos is a coastal city. It is bordered to the south by the Atlantic Ocean. But is the ground level of the city lower than that of the sea?

We checked several sources that list places in the world below sea level. Lagos was not on any of them.

The elevation figures we found on the flood map for Lagos ranged from one to 50 metres above sea level. The map showed elevations of about one metre in areas around the coastline and lagoon, and higher elevations further from the coastline, Lagos Lagoon and rivers.

For instance, in Lagos’s capital, Ikeja, in the northern part of the state, the elevation ranged from about 25 metres above sea level in Alausa, where the governor's office is located, to about 50 metres in Ogba.

“I am not aware of any place in Nigeria that is below sea level,” Imo Ekpoh, a professor of climatology at the University of Calabar in southern Nigeria, told Africa Check.

“There are scholars, especially at the University of Lagos, who have been studying the elevations around the sea and the Lagos lagoon for many years. If Lagos was below sea level they would have published this information,” Ekpoh said.

Stressing the importance of Lagos, Sanwo-Olu also said the city controls 65% of international air traffic in and out of the country.

He also didn’t specify whether he was referring to the share of international flights into the country that land and take off from Lagos or the total number of passengers. Traffic could also refer to cargo – including by sea.

The most recent air transport data published by the National Bureau of Statistics dates back to 2021. It includes data on the number of passengers on international flights arriving at or departing from Nigerian airports.

According to the data, about 1.11-million passengers arrived in Nigeria on international flights in 2021. Of these, 787 874, or 71%, landed in Lagos.

About 1.11-million passengers also left the country on international flights, of which 807 648, or 72%, departed from the international airport in Lagos.