ECML 2026

The ECML 2026 Challenge is the newest competition around the Flatland environment.

• Follow the starterkit to make your first submission.

• Read about the evaluations metrics of this edition.

• Read about the level configurations of this edition.

⏱ Timeline

• Competition start: May 4th, 2026

• Competition end: June 29th, 2026 (AoE) (new!)

• Winner announcement: July 6th, 2026 (new!)

🗺️ Topology

The competition runs on a single topology (120 x 150) with 28 stations:

All 28 stations are provided in stations.pkl. 6 lines that are used in the evaliation are also given as examples in level_o_scenario_1.pkl.

The map is subdivided into five scenes (i.e. regions):

The scenes correspond to the scenarios in each level with the exception of level 6, where all five scenarios use scene 5 ( cf. level configurations).

Competition features:

• Intermediate stops: the lines have intermediate stops. The environment does not enforce agents to pass by intermediate stops, but agents (trains) are penalized if they skip intermediate stops are do not respect time windows defined for intermediate stops, see ECML 2026 Evaluation Metrics. Intermediate stops are defined by a set of alternative grid cells in the same station.

• Speeds: the agents always run at their train category’s max_speed<=1.0 or at zero, we do not use variable speed in the competition (i.e. acceleration_delta=1.0 and braking_delta=-1.0 see Actions)

⭐ Supported Flatland Versions

You must use Flatland version 4.2.5 or 4.2.6.