Defence Terrain Research Laboratory (DTRL) is a laboratory of the Defence Research and Development Organisation (DRDO). Located in Delhi its primary function is research and development of techniques to evaluate terrains and assess mobility potential of inaccessible areas. The Defence Terrain Research Laboratory focuses on providing state-of-the-art terrain intelligence to the armed forces.
The DTRL's origin dates back to 1964 when a Terrain Evaluation Cell (TEC) was set up as a unit of the DRDO. The cell's objectives were to develop techniques needed for evaluating terrain and assessing the mobility potential in inaccessible areas. It became a full-fledged laboratory in 1981, and was renamed the Defence Terrain Research Laboratory.