Recommendation: make it easier to switch from metric measurements (i.e. kilometers) back to US measurements

Hi folks, I live in Silicon Valley. In Firefox I looked for some stores in Germany for my sister who lives there. Right away Yelp began displaying distances in kilometers even when I searched for stores in Bay Area counties. Turns out Yelp switched its country setting from USA to Germany (and began listing distances in kilometers).

And now just a few minutes later, Google Maps on a different browser! (Chrome) on the same computer has also switched to kilometers. I did not do any searches for stores in Germany on Chrome, so it must have picked up the setting change from the Mac OS.

This has happened to me before when I try to order books on Amazon's German site for my nephews who live in Germany.

There’s got to be an easier way to switch EVERYTHING back to US measurements such as miles. Easier for traveling. I think this option should be included in the Languages & Region control panel. HELP! I use 4 browsers on a regular basis and this this is a big nuisance to fix not only in different browsers but different individual sites.