Driving from Salzburg to Prague in July

Yes it is safe - the days of highwaymen and robber knights are at least 200 years in the past. Ok, you mean, are the roads navigable? Well, I can assure you that so long as you can drive at 80 mph on the Autobahn (be sure your rental car has a Vignette sticker) you will hightail up to Linz. From there you can go directly north through Bad Leonfelden (careful, my home town, and I am visiting there at the same time) into CZ.
In short order, Vyssi Brod/Hohenfurth, Cesky Krumlov/Krumau (gotta stop there), on to Ceske Budejovice/Budweis. Stop and park; visit the center of town. It's a large, industrial city, but the center is worth it. If time is of the essence, head up on the main highway through Tabor (medieval town center) into the freeway system taking you to the nearest Prague traffic jam.

Czech roads are well-maintained, and so long as you watch your speed through towns, you will not have any problems. Coming up from the border you may see more bikers and hikers, since the Böhmerwald/Sumava is a prized recreation area.

After experiencing heavy traffic in the 1990s, Bad Leonfelden at last constructed a bypass, but if you want to see another pretty spa town not yet discovered by the RS crowd, stop on by!

Martin,

Thank you for your suggestions! I have never been to Czech Republic and had no idea what to expect. I googled the cities you told me about, they are beautiful! I think we'll have to make a couple extra stops on the way to Prague.

Thanks again!
Tina

We just returned from Prague - Linz run and can tell you we were pleasantly surprised. The roads are better than we have in MO. Easier to navigate by far than rural France - better marked. The guidebooks recommend secured parking but that was not an issue for us.

Thanks for the info! I have another question - did you just have your American driver's license or did you get an International driving permit?

Thanks!
Tina

Tina, make sure your car rental company will allow you to drive the car in that country. Last year Auto Europe required us to initial a statement on the rental agreement that we will not take the car into any former Eastern block countries. Have a great trip.

Thanks! We checked with Hertz, they said as long as we don't rent Mercedes, Audi, BMW or Volkswagen we should be fine. What kind of car did you have when you had to initial you wouldn't take it over?

Tina, we rented the car through Auto Europe (the broker), but it was the Avis rental car agency. We had a diesel VW Gulf. By the way, we got 56 miles to the gallon (we did the conversion) around town (not the autobahn) with the AC on. I know you'll need a larger car for your family, but reserve a diesel if you can.