There is a Wi-Fi dead zone between my house and where I sit in my car. That means that when I'm buckled in and about to head out, my phone is technically connected to the house Wi-Fi, but can't really connect to the web. I tell it to get me directions somewhere, and it just kind of sits there, spinning and pretending, like a kindergartner with a bunch of chores to do.
There was, at one point, a solution for sometimes-offline situations like that. There used to be a "Make Available Offline" option available upon pressing the Menu button, which would ask you to box in the area you wanted to save. But ever since Maps got an update—to roughly version 6.9 or 7.0, but for most people, to the "New Maps" with the little tab on bottom left—that option has been gone. Or, really, just hidden away in a strange Easter-egg-esque little expression, one that is thankfully also easier to set up on iPhones, iPads, and Android devices.
Open up Maps, then get to the area you want to save for offline viewing, searching, and directions. Pinch and zoom until a good area is covered. You can't do too much, or else Maps will fail to save it (sometimes with an error message, sometimes just by failing to hit 100% saved). Wired reports that saving the entirety of California did not work. I found that I could pretty easily save the city of Buffalo, NY, but trying to bring in all of its suburbs (basically the entire county) caused Maps to stall at 99 percent saved.
In any case, once you have a decent area saved, either around you currently or around where you want to go and explore, type or say this into Maps: "OK Maps," or "Okay Maps."
That's it. Whatever area you had visible in the Maps window will now be saved offline. You can search through it for businesses and landmarks, get directions to places inside the grid, and pan and zoom around, when you are in Airplane Mode or just without a constant web connection. It's handy for ensuring local directions around town, for traveling to cities where you may or may not have a SIM card for data, and for making tablets without data plans useful as navigation tools.
Note: Tech blog Engadget claimed back in July that Maps, or maybe Now, would have a "Make this map area available offline" button, but that doesn't seem to occur in Maps as it looks today.