In reply to dilatory:
Last two years we've used a walking backpack with kit in (and toddler) on person 1, person 2 with a pair of mats and water/food. No issues getting between places. We've always just found somewhere to set up as a base - rotated child duties - got a lot of climbing in.
We have used bikes and trailer to access some places, worked well. We've considered a garden trailer with wide tyres before, but never bothered. Seen quite a few other people using them to great effect though.
1st time 1 year old learning to walk - was great, she was using the boulders as handrails and sticks as walking poles.
2nd time 2 year old - exploring, looking at everything, but happy to wander around near us - she's not a run away type. Except when there are lizards - they must be chased at all times. She got quite a bit of climbing done too - easy angled boulders she wanted to then slide down.
3rd time in April coming, she'll be three - expect she'll want to do a lot mure "climbing" so we will factor that in. BUt quite a few of us going, other kids too.