Most of us probably walked through the Glowing Sea, Fallout 4's most irradiated area, decked in Power Armour or a Hazmat suit. Because we're wimps, apparently. Watch as stanleyx2002 braves the entire Glowing Sea without a single piece of armour or weapon. Judging from the commentary, Stanley didn't really think he could do it!
Somehow, though, he makes it all the way to Virgil's house in one piece. This of course required running away from a number of terrifying monsters, such as Deathclaws and legendary enemies, but still. It's possible.
Worth noting that the character is in the '60s, levels-wise, and also has a perk that allows for radiation resistance -- that's why this is possible in the first place. Turns out, with the right build, you basically become a Child of Atom in Fallout 4. Neat.