NS (Nederlandse Spoorwegen)

NS API provides reliable Dutch railway data with straightforward API key authentication and good documentation through their developer portal.

The RESTful API covers train schedules, journey planning, disruptions, and station information comprehensively. Real-time data is accurate and well-structured, with multiple community libraries available. However, it's specific to Netherlands rail travel and requires understanding of Dutch transport concepts.

The API is free but focused on passenger information rather than booking. It's excellent for travel applications in the Netherlands, offering authoritative data from the national railway operator with strong developer community support.