Old railway allignment now a road?

[stephen@midac.splat.spam.com.au (stephen)]

In years gone by I travelled the Harden/Yass road many times, but not 
for quite a while now.

Travelling east from Binalong to Bowning (as I recall it) the road 
bridge crosses the railway at Illalong Creek. There then appears to be
old railway embankment on the right side of the road. The road then 
appears to run along the old alignment through a series of cuttings 
and thence onto a high embankment. At the end of the high embankment 
the road swings to the right and the rail alignment appears to go 
virtually straight ahead.

I have 2 questions which used to occur to me almost each time I 
travelled the road:

1. When was the railway re-aligned to its present alignment?

2. At the Illalong Creek end of the old alignment I have never been 
able to work out where the railway went next and/or how it rejoined 
the present alignment.

Can anyone shed light on this for me?

Regards,

Stephen