[6] A significant delay in construction was experienced at a site that became popularly known as Devil's Terror - a location between Darlington and Glen Forrest.

The rail alignment had to be moved 100 metres south along the bed of Nyaania Creek, which was diverted into a specially constructed channel.

[5] It soon became apparent that the section between Bellevue and Mount Helena was too steep for the increasingly heavier trains and engines required for the route.

[5] It increased railway capacity to the east, while offering less demanding grades and improved safety compared to the alignment of the first route.

This work also involved gauge-converting the remainder of the line as far as East Perth, as well as the Kwinana freight railway to dual gauge.

It was later upgraded using heavy (60 kg or 132.3 lb) continuously welded rail laid on new concrete sleepers during the late 1970s through into the early 1980s and can now accommodate axle loads up to 41 tonnes.

The original section from Fremantle to Guildford (and onwards to Midland) is still in use as part of Transperth's suburban passenger rail network.

Transwa's AvonLink, MerredinLink and Prospector rail services use the line from East Perth to Northam, Merredin and Kalgoorlie.

[22] Former named trains to previously traverse the line (predominantly the Second Route) were The Westland, The Kalgoorlie, The Mullewa, the Albany Progress and the Trans-Australian.

The original Eastern Railway alignments still survive today, in the form of a rail trail for cycling, horse riding and walking.