If you take Bells Line of Road, there are the Botanic Gardens at Mount Tomah.
If you come up Bells Line Road instead of the highway, Mt Tomah Botanic Gardens are well worth a stop. If you are using the highway, Blackheath has a few interesting cafes and the pub actually does a good counter lunch.
Our port of call is usually in Leura, for coffee and to stretch the legs. Nice little village feel.
We stepped foot into The New Ivanhoe Hotel once and it was like being in a nursing home.
The Gardners Inn at Blackheath did a good counter meal, and some of the local youth fired up some dj decks in the "beer garden". Nice, different, unusual way to break up the trip...
I'm another for either Mt Tomah or Blackheath.
The Bells line makes for a great drive and if you time it right (after late 2017) you have the added attraction of possibly having the zig zag rail chug along beside you.
Blackheath has become very popular and there are some great little cafes off the hightway.
Don't be tempted to stop at the Hydro.....
My favourite is in the street that runs parallel to the highway (sorry don't know the name)
Bakehouse on Wentworth, GW?
Mt York, a short drive from Mt Victoria, site of descent from the BM of first road across the mountains. I saw a recent episode of UK Who Do You Think You Are on Jason Donovan, whose ancestor was William Cox, the amazing man who supervised the building of the road. The episode was basically the story of the road build. Excerpts from Cox's and Macquarie's diaries about the road are fascinating. You can still walk the road down Mt York. It's not particularly well maintained, a real shame given its great significance in opening up inland Australia.