THE Estela de Luz (“stele of light”) is not one of Mexico City’s glories. The 104-metre (341-foot) tower, built from panels of quartz, was supposed to celebrate the bicentennial of Mexico’s independence from Spain in 2010. But it was inaugurated in 2012, 16 months later than planned, and cost 1.3bn pesos ($100m) to build, more than treble its original budget. The federal government paid the bill. Eight former officials involved in the tower’s construction were arrested after its completion.

The delay and cost overruns earned the tower a place on the “Corruptour”, a new twice-a-week bus tour that shows off the capital’s monuments to graft, fraud and mismanagement. There are plenty of them. Tourists board a converted school bus, stripped of its roof and emblazoned with tabloid-style headlines, and visit ten sights, or nine when the traffic is bad. They include the Balderas metro station in the city’s centre. A recorded commentary tells the saga of the metro system’s Line 12. Its stations were so shoddily built that half of them had to close temporarily.

The bus pulls up at the institute of social security, Mexico’s third-biggest public-sector purchaser of goods and services. The taped commentary explains that, according to a report in 2011, the institute was paying a third more than it should because its suppliers colluded with each other. (It has since improved its procurement practices.) The stop outside the interior ministry is an occasion to talk about impunity. The ministry is responsible for the maximum-security prison from which Joaquín “El Chapo” Guzmán, a drug kingpin, escaped in 2015, down a tunnel dug from the shower in his cell. That led to the arrest of 13 officials. Mr Guzmán was eventually recaptured and extradited to the United States.

The Corruptour was dreamt up by a group of friends working for NGOs. “Everyone knows about corruption but imagines it is a monster,” says Patricia de Obeso, an organiser. “We’re trying to break it down and explain how it’s done.” The tourists, a mix of Mexicans and visitors from elsewhere in Latin America, do not buy tickets but are asked for donations.

The Corruptour is not the only gimmick for drawing attention to a problem that is indeed a monster (on average households spend 14% of their incomes to pay bribes and meet other corrupt demands). The tour was inspired by a similar one in the north-eastern city of Monterrey. The Mexican Corruptionary, published last year, offers definitions of 300 corruption-related terms. A góber covers up for policemen in the pay of organised crime; a hueso (bone) is a bribe paid to get a public-sector job that itself offers bribe-taking opportunities. In 1996 the word “corruption” appeared in 27 Mexican headlines, according to Mexicans Against Corruption and Impunity, a think-tank. By 2015, with newspapers reporting on police who had taken part in the massacre of 43 students and on allegations that the president’s wife had bought a house from a government contractor, the number of corruption-related headlines had jumped to 3,500.

Ms de Obeso encouraged the tourists to vent their own feelings about corruption. Luis, from the State of Mexico, which surrounds the capital, took the microphone to declare that Mexicans are “living in a time of crisis. People need to inform themselves.” But others on a sunny Sunday afternoon seemed to be more interested in snapping photos. They were not about to let their indignation get in the way of a good selfie.