The line is identified as U4. You can find this designation on metro maps, signs in passageways, platform information boards, and transport apps. Before boarding, always check not only the line number or colour, but also the final destination of the train — this will help you avoid boarding a service heading in the wrong direction.

This metro line runs through Vienna (Austria). Metro lines typically connect several parts of the city — from residential neighbourhoods to business districts and the city centre. To find out whether this line suits your journey, open the metro map and check the station locations relative to your destination. Sometimes one transfer is more convenient than searching for a direct route.

The average interval between trains is 3. During peak hours trains run considerably more frequently, while late in the evening and at weekends the interval is typically longer. If your journey is time-sensitive, it is worth checking the current schedule in the operator's app or on the information boards at the platform.

The line is operated by Wiener Linien. This organisation is responsible for train services, station condition, safety, and infrastructure. If you encounter any issues — delays, technical problems, or ticketing queries — please contact the operator directly. Providing your station, direction of travel, and the time of your journey will help them handle your enquiry more quickly.

This line is part of the «U-Bahn Wien» network. Within a single transport network, the same fare rules, ticketing, and transfer policies typically apply. This means one ticket or travel card may be valid across multiple lines in the network without requiring an additional payment when changing trains.

Operating hours for this line: 05:00-00:30; Sa,Su,PH 00:30-00:30. The times of the first and last trains may differ on weekdays, weekends, and public holidays. Before a late-night journey, we recommend checking the last departure time in the official app or on the operator's website to make sure you won't be stranded without transport.

On metro maps, this line is shown in #029540. Colour coding is the primary navigation aid in metro systems — it helps you quickly identify the right direction on signs, maps, and information boards. When making transfers, always pay attention to the line colour to avoid confusing platforms or directions.