Milan's Duplicate Image Problem: What It Means for Residents Trying to Navigate the City Online

A quiet but growing problem is disrupting how Milan's residents interact with the city's digital infrastructure. Duplicate images — the same photograph appearing multiple times under different addresses, dates or descriptions — have accumulated across dozens of municipal and commercial platforms, from the Comune di Milano's official civic portal to private real estate aggregators listing properties in Porta Nuova and Isola. The result is a patchwork of conflicting visual information that residents, newcomers and tourists alike are increasingly struggling to parse.

The timing matters. With the Milan-Cortina 2026 Winter Olympics now weeks away and the city expecting a surge of international visitors, officials at the Comune and operators along Corso Como and the rebuilt Navigli canal district have been pressing to audit and update digital assets tied to public spaces, event venues and transit infrastructure. Stale or duplicated images of metro stations, event spaces and key commercial streets do not just mislead — they erode confidence in official sources at the worst possible moment.

Where the Problem Shows Up

The issue surfaces most visibly in two places. First, on the Comune di Milano's open-data portal, which hosts tens of thousands of geotagged photographs of public infrastructure, parks and cultural heritage sites. Archivists and civic tech volunteers working through the city's PartecipaMi engagement program have flagged that images uploaded during separate cataloguing drives — including a major push in 2021 and a follow-up round in 2024 — produced significant overlap, with some locations in the Brera neighbourhood and along Via Tortona appearing under three or four separate entries with no deduplication applied.

Second, in the private real estate and short-term rental market. Platforms operating in the Porta Nuova district, where new residential towers have been listed and relisted as units change hands or management companies rotate, regularly surface the same interior photographs under different addresses or unit numbers. For a prospective renter or buyer navigating the market near Piazza Gae Aulenti, that duplication can mean comparing two listings that are, in effect, the same apartment photographed years apart — with no clear indication of which image reflects current conditions.

Civic tech researchers have estimated that in large European cities with comparable cataloguing histories, duplicate image rates on municipal open-data portals can run as high as 15 to 20 percent of total uploaded assets. Milan's PartecipaMi program, which has been running annual data-quality sprints since 2022, has not yet published a specific figure for the current duplication rate, but participants in the most recent sprint — held in March 2026 at the BASE Milano creative hub on Via Bergognone 34 — described the scale as substantial enough to require automated tooling rather than manual review alone.

What the Clean-Up Effort Looks Like in Practice

Deduplication is not a trivial exercise. Each flagged image must be cross-referenced against its metadata — geolocation, upload date, contributing user or institution — before it can be merged, archived or removed. For photographs tied to listed cultural heritage sites, such as the Palazzo della Ragione or the Arco della Pace, errors in that process carry genuine preservation risk: delete the wrong version and you may lose the only high-resolution record of a restoration phase.

The practical advice for residents is straightforward. When using the Comune's portal or any third-party platform to research a local address, check upload dates and cross-reference against at least one secondary source — Google Street View history or the city's own Geoportale Milano, which is updated on a rolling quarterly basis and carries a visible timestamp on each asset. For renters dealing with property listings in high-turnover zones like Città Studi or the redeveloped Scalo Farini corridor, requesting fresh photographs directly from the landlord or agency before signing remains the most reliable safeguard.

The Comune has indicated that a wider digital asset audit is planned for the third quarter of 2026, timed to follow the Olympic period. Whether it addresses the duplication backlog comprehensively will depend on resources allocated after the games conclude — and on whether the momentum generated by PartecipaMi volunteers carries into official policy.