By the early 1880s, a thriving quarrying industry had established itself in northern Leicestershire, working an outcropping of Marlstone that ran north-east from the village of Holwell to the edge of Belvoir Castle.
[2] In November 1883, the GNR applied for a second act, extending the Eaton Branch to "...a field belonging to, or reputed to belong to, His Grace the Duke of Rutland... adjoining the road leading from Belvoir to Eastwell, at a point about 220 yards measured in a north-westerly direction from Shelton's Barn.".
The Holwell Iron Company was quarrying the ore fields to the south and west of Eaton village, while the Waltham Iron Ore Company worked fields that stretched to the west and north of the branch's northern terminus.
[4][5] North of this siding there was a timber viaduct on the Eaton Branch, which was filled in during 1955 with slag from Holwell Iron Works to form an embankment which can still be seen.
Once more entering a cutting, the railway passed under the Belvoir Road at the junction with Toft's Lane, and terminated in a run-round loop and sidings serving the loading stage of the Waltham Iron Ore Tramway.