It is indeed quite a long ride, I think the mentioned 30 minutes seems about right. As for conditions, our tire actually flattened due to the potholes, so make sure to drive very carefully!
We were there a few days ago. No 4wd necessary but the road is rough due to potholes. I would say it's about 30 min from scenic. Though in the morning you will leave the other way to join the paved road and it's a shorter ride.
Its a far distance from the main entrance to the park south of Wall. For road conditions, best to ask a park ranger the day of. Road conditions can change in a very short time frame.
It's rather long. Probably a couple of miles. It had been rainy when we got there and was still passable. We were in a 4wd truck, but remained in 2wd.
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