Metroad 9

A9 New South Wales
The Northern Road (northbound) at Luddenham
Type	Highway
Length	61 km (38 mi)
History	Superseded Metroad 9 in 2013
Route number(s)	A9 Entire length
Former route number	Metroad 9 (1998-2013) State Route 69 (1973-1998) Entire length
North end	Windsor Road (A2) Wilberforce Road (Putty Road) Windsor, Sydney
	Richmond Road (B59) Hawkesbury Valley Way Great Western Highway (A44) M4 Western Motorway (M4) Elizabeth Drive Camden Valley Way Camden Bypass
South end	Hume Motorway (M31) Narellan Road (B69) Campbelltown, Sydney
Major suburbs	Windsor, Campbelltown
Highways in Australia National Highway Freeways in Australia Highways in New South Wales

The A9 is the outer western Sydney Bypass connecting Campbelltown to Windsor. It was formerly designated Metroad 9, which was one of Sydney's Metroads

The name "A9" is just the route allocation for the route as a whole. In fact, the A9 route runs along a whole series of roads. From Windsor to Campbelltown:

The A9 applies to Narellan Road from the Hume Motorway interchange to Camden and the complete stretch of The Northern Road from Camden to Windsor via Penrith. It crosses the Great Western Highway and M4 Western Motorway near Penrith.

The A9 is also the major link between the International Regatta Centre at Cranebrook and the M4 Western Motorway. It was upgraded just before the Sydney 2000 Olympics.

The A9 route was first known as State Route 69. State Route 69 was a state route linking Singleton to Wollongong via Sydney's western suburbs, along Putty Road, the current A9, and Appin Road. It was replaced by Metroad 9 in December 1998 and consequently State Route 69 was split into two sections. The northern section (Putty Road) connected Windsor to Singleton. The southern section (Appin Road) connected Campbelltown to Wollongong via the Princes Motorway.

...
Wikipedia