The Train Describer feed provides low-level detail about the position of trains and their train reporting number through a network of berths. Usually, but not always, a berth is associated with a signal - but there are locations (such as terminal platforms at stations) where there may be more than one berth. From each berth, there are zero or more other berths which a train description may step in to. A step between berths represents movement of the train from one berth to another. Some of these steps may be one-way, some may be two-way.

To access the TD data feed, you must select and subscribe to the appropriate geographical topic(s) on the My Feeds page on the Data Feeds website (see the about the feeds page.)

See also the list of train describers page.

Topics

ActiveMQ topics are provided for signalling in specific geographic areas, as well as a topic representing all TD data in the country.

Topic	Description
TD_ALL_SIG_AREA	All signalling areas
TD_SE_SIG_AREA	Scotland - East
TD_SW_SIG_AREA	Scotland - West
TD_LNE_NE_SIG_AREA	London North Eastern - North East
TD_MC_EM_SIG_AREA	Midlands & Continental - East Midlands
TD_LNE_GN_SIG_AREA	London North Eastern - Great Northern
TD_LNW_LC_SIG_AREA	London North Western - Lancashire and Cumbria
TD_LNW_C_SIG_AREA	London North Western - Central
TD_WCS_SIG_AREA	West Coast - South
TD_ANG_SIG_AREA	Anglia
TD_KENT_MCC_SIG_AREA	Kent and Midlands & Continental
TD_SUSS_SIG_AREA	Sussex
TD_WESS_SIG_AREA	Wessex
TD_WTV_SIG_AREA	Western - Thames Valley
TD_WWC_SIG_AREA	Western - West Country
TD_WWM_SIG_AREA	Western Wales and Marches

Message types

The Train Describer feed has seven message types, split into two classes. See individual pages for further details.

C-Class Messages provide information about train describer berths and descriptions
S-Class Messages provide signalling state information