Main water valve hidden in wall - I assume?

[Andrew S.]

I have a 1935 house that has the water pipes coming out of a common center wall to the kitchen on one side and bathroom on the other side of the wall. I assume the main water valve is behind the wall on both sides, before it tees off to the kitchen, bathroom, and water heater. I'm doing a minor renovation of the house now, is it worth busting open the wall behind the water heater to locate the main water shutoff valve? The water heater, kitchen sink, and bathroom all have their own valves so I don't think I need to worry about it. But I currently have no way to replace a valve if I wanted to. This probably falls under the category of if it's not broke, don't fix it. Thanks.