🚍 Cermonews #10 | Do We Really Have a GTFS Data Format in Public Transport?

Parabol
May 16
5 min read

Hello! With the 10th issue of Cermonews, we are thrilled to meet you for the tenth time. In every edition, we focus on an important topic in public transport, and with your comments, contributions, and questions, this series continues to grow stronger together with you.

In this issue, we turn our attention to a critical element in the digitalization of transit systems and the international standard for data management: GTFS (General Transit Feed Specification).

What is GTFS?
Do we really have GTFS in public transport?
What does GTFS provide?
Cermoni’s GTFS conversion

With these newsletters, our goal is to present technical knowledge in a simple and accessible way, producing content that contributes to the sector.

As always, we continue with our regular sections—“News from Us,” “Cermopedia,” and “Behind the Scenes”—to share the latest updates and introduce the dedicated colleagues behind Cermoni.

So, let’s open up the GTFS file together!

What is GTFS?

GTFS (General Transit Feed Specification) is an open data format that enables public transport systems to be represented digitally. It contains the fundamental components of a transit system such as stops, routes, timetables, and trips. Today, GTFS is widely used by municipalities, transport operators, digital mapping services, and mobility companies around the world.

GTFS consists of two main parts: GTFS Schedule and GTFS Realtime.

GTFS Schedule includes files for routes, timetables, fares, and transfer details.
GTFS Realtime provides dynamic information such as vehicle positions, delays, and service alerts, allowing real-time updates for passengers.

With GTFS, city transport data can be visualized on digital maps and shared seamlessly across applications. GTFS not only ensures digitalization, but also makes data accessible, editable, and analyzable. By keeping public transport data in a standard format, cities create databases that are easier to manage and integrate.

Do We Really Have GTFS in Public Transport?

Many transport authorities and operators believe they already have data “in GTFS format.” However, in most cases, this is only a superficial resemblance to the GTFS file structure. Simply combining CSV files is not enough.

For true GTFS compliance, the following must be ensured:

All core files (routes.txt, trips.txt, stop_times.txt, etc.) are created correctly and consistently.
Data includes temporal and spatial completeness, aligned with the service model.
A functional logic chain is established between schedules, routes, stops, and trips.
The dataset is tested and validated against real-world use cases.

Without these conditions, data may look like GTFS but not actually function as GTFS—leading to failures in integration with third-party systems, planning software, and passenger applications.

What Does GTFS Provide for Public Transport?

GTFS significantly enhances the passenger experience by providing accurate, real-time information. Passengers can check bus arrival times, routes, and transfers directly through mobile apps. Especially in large cities, GTFS powers trip planners and digital maps, reducing travel time and uncertainty.

For operators and municipalities, GTFS is a powerful tool for planning and monitoring. It enables adjustments to timetables, demand analysis, and service optimization. The open-data nature of GTFS also facilitates collaboration among stakeholders, helping improve systems more quickly.

Without a standardized format like GTFS, each city would maintain its own data structure, making system integration complex, time-consuming, and costly. This would hinder data sharing, slow down analyses, and limit the benefits of digital tools for both institutions and passengers.

That’s why at Cermoni, we work to transform city transit data into GTFS-compliant datasets—ensuring integration, analysis, and sustainable use.

Cermoni and GTFS Conversion: More Than Just a Format

Cermoni does not simply convert scattered, raw data into GTFS format. It also ensures the dataset is functional for planning, analysis, and integration. In this way, GTFS becomes not just a technical requirement but a strategic data infrastructure.

In Cermoni’s GTFS conversion process:

Dispersed data such as stop lists, route definitions, and timetables are analyzed, missing or incorrect fields are identified, and structural consistency is established.
Beyond technical validity, operational logic is also verified. For example, mismatches between service calendars and trip definitions, or inconsistencies between route start and end points, are detected and corrected.
GTFS packages are generated to be directly compatible with external systems and tested against predefined scenarios.

The result is a forward-looking infrastructure, ready for future planning and analysis tools—eliminating the need for repeated conversions.

Common Misconceptions About GTFS

“If we merge timetables and route geometries, we have GTFS.”
❌ Wrong. GTFS is not just a file structure; it is a data standard. CSV files may look like GTFS but cannot guarantee correct interpretation or integration.
“Each agency can create its own GTFS format.”
❌ Wrong. GTFS is universal and does not change from agency to agency. It was developed by Google Transit and is openly documented to ensure consistency across systems.
“Creating GTFS is purely a technical task.”
❌ Wrong. GTFS is not only about file creation but also about ensuring that the data makes sense from a transport planning perspective. Inconsistent calendars, inaccurate trip durations, or incorrect stop sequences may technically validate but still fail functionally.

📰 News from Us

Join us at the UITP Global Summit 2025 in Hamburg!

🌍We’re excited to announce that Parabol will be present at the UITP Global Public Transport Summit, 15–18 June in Hamburg! You can find us at Hall 3 – Stand A337, where we’ll showcase Cermoni’s solutions—from GTFS conversion to driver shift planning and deadhead minimization.

We are also part of the “Innovation Guided Tour”, giving a live demo, and our Marketing Director Tuğçe Işık will be sharing our digitalization project experiences from different regions on stage.

We Attended Turkey’s Largest ITS Event – ConfITS25!

Conf-ITS25 took place on April 16–17 in Ankara. We had the chance to connect with industry stakeholders and present our innovative solutions for sustainable, safe, and connected mobility. Thank you to everyone who visited our stand!

Turkey’s First Metropolitan SUMP Project Completed in Izmir! 🌍

We’re proud to have completed Turkey’s first Sustainable Urban Mobility Plan (SUMP) in Izmir, which also marks the country’s first application of an Activity-Based Model (ABM) at the metropolitan scale.

Safely Project Field Visit in Konya 🚦

Supported by EIT Urban Mobility, the Safely Project held a recent field visit in Konya, with partners from Parabol, Konya Metropolitan Municipality, Sarajevo Canton Ministry of Transport, and TU Berlin. The visit included technical tours, safety presentations, and training sessions using the Safely platform.

✨ Cermopedia: GTFS Explained

In the new episode of our Cermopedia series, we explore GTFS—what it is, why it matters, and how it powers digital transit systems. Our colleague Yağmur Gülbaz, Industrial Engineer specializing in public transport algorithms, explains the essentials in a short and accessible way.

🎥 Watch the video here → https://www.youtube.com/watch?v=BKoyhxi_bOc&feature=youtu.be

Behind the Scenes 🙌🏻

In each issue, we introduce a member of our team. This time, meet Özgün Akbaş, our Marketing Specialist at Parabol, who plays a key role in bringing Cermoni’s solutions to cities.

“For me, Cermoni is more than just software—it’s a real transformation tool for public transport management. Every presentation and every piece of content we produce shares the same goal: promoting data-driven, sustainable, and user-friendly solutions for better mobility.”

Have You Started Using GTFS in Public Transport?

GTFS is a key step in the digitalization of public transport. Where does your city stand in this process?

Some cities have already adopted GTFS, while others are just beginning. As Cermonews readers, we’d love to hear your experiences—what challenges or needs have you encountered?

Your contributions make this newsletter even more valuable.

Thank you in advance! 🙌🏻