Best Low-Tech Ways to Purify Water in an Emergency

[ChrysanthiDream]

When it comes to emergency water purification, there’s a lot of tech-heavy gadgets out there, but what worries me is what happens if batteries die or filters run out? I’m looking to really focus on the solid, low-tech methods—things that could be done with basic household items or even out in the bush with minimal supplies.

I know about boiling (rolling boil for at least a minute), and