These roads, together with London Street further north, form State Route 61,[1] which links Crawley with West Perth and Yokine.

[11] In 1939, there were calls for the road to be rebuilt and upgraded to dual carriageway standard in the vicinity of Kings Park.

[13] Thomas Street's southern terminus is a traffic light controlled intersection with Winthrop Avenue and Aberdare Road in Shenton Park, at the north-eastern corner of the Queen Elizabeth II Medical Centre, where Sir Charles Gairdner Hospital is located.

The road follows the edge of Kings Park for 2.1 kilometres (1.3 mi) as a six lane dual carriageway, heading in a north-easterly direction to West Perth.

The road's northern terminus is situated 600 metres (2,000 ft) further northeast, at its intersection with Loftus Street and Railway Parade.