That looks like it. Some call it crazy paving. It usually gets laid over compacted paving sand/s. The joins between each flagstone are usually concrete with the edges concreted so it stays in place. I have seen some with sand between the joins which also looks good. New sandstone from Gosford Quarries looks superb but is expensive. (its a great product!). I'd look for some second hand stuff on Ebay/Gumtree/etc.

annb1997 - Yes, that is part of the reason I'm doing this project. The entire area will be lowered, re-graded and some drains installed (the garden edge is kind of temporarily in place for now, got a great deal on the plants so they had to go in). It's a bigger job than anticipated as it also means the air conditioners (x3) need to be de-commossioned and re-installed at the new levels. John, I like the idea with regard to the tank, but we get allot of bitey critters and I don't really want to give them anymore areas to hide out in.

Hi mluh You've obviously done your research on these products, so it's most likely going to come down to personal preference. As you've mentioned, a natural stone is going to come with an amount of maintenance but the beauty of Travertine is within its variation. Once sealed with a good quality sealer (I recommend Guard Industry), the maintenance is really quite low and most spills are lost within those natural variations. 99% of spills can be cleaned up without too much trouble. Porcelain, on the other hand, can be quite difficult to clean once it's been marked. That said, the external porcelains have a great non-slip texture and are very hardy when used as paving/tiles. I'm personally not a fan of using them as pool coping, but many people love it. Again, both have their advantages and disadvantages so I would recommend using the product that you're happy looking at for the next 10-20 years. - Jordan

I saw these today and they seem to match well with our wall bricks and roof colour and well priced too. Now I think I'll consider retaining wall options and compare to brick. https://tilemarket.com.au/product/trevi-grey-external-300x300/ Edit: definitely going with brick I think