The site consists of a circular concrete slab with lowered centre. It was used for heating iron wheel rims prior to them being fitted.
The Wheel Rim Shrinkage Pit was constructed in about 1917 adjacent to the blacksmith's shop in the township of Emungalan on the northern side of the Katherine River. The Wheel Rim Shrinkage Pit was a crude forge used by a blacksmith to heat and expand iron tyres prior to them being fitted to wooden wagon wheels. Once fitted, the iron tyre was quenched with water thus shrinking it and forming a tight fit around the wheel. The Wheel Rim Shrinkage Pit marks the spot where the township of Emungalan developed as a result of the extension of the North Australia Railway from Pine Creek to the northern side of the Katherine River. The pit is one of a few items of physical evidence of the town's existence. It is a tangible reminder of the role wagons, drays and buggies played in the early exploration and settlement of the Territory and is a direct link to our early transport system.