Finding valve boxes: It seems typical that one might be near the water main, but certainly does not need to be. We have three boxes with on being relatively close in the front and the other two in the back. I will likely add another in the back. None of them are very close to each other and they are not that big so they hold up to three valve each. Valves do not necessarily exist in boxes, but I really like them in them.
It appears that you have six zone which would be six valve. The first image looks like a main with anti-syphon. The second definitely looks like a valve in a box. Do you have six individual boxes? It is hard to tell, but it looks like all the wires go into this box, which means they probably continue to the next box. If so, the wire to that valve might not continue to the next, but the common does need to be hooked up and continue on to each valve. Are the boxes next to each other or spread out? Since none of them are working, I would start with the first valve that the wires go to (if you can tell which that one is, otherwise, you might have to check all). Has any digging occurred or work where the wires go from the controller through outside?