I'm planning a five day national parks road trip for our family (parents plus 2 boys aged 11 and 15) next September as part of a month long visit to the US from Australia.
We plan to leave from Las Vegas, drive to South Rim Grand Canyon then up to Zion or possibly Bryce then back to Vegas. Given time is short, is Bryce or Zion a better choice or should we try to do both? What differences are there in what we will see? Zion would involve less driving so I'm tending to that but would like advice.