Fountain Paint Pots

The 'Fountain Paint Pots' sound friendly, but they're actually boiling mud pits.

This is the approach to the 'paint pots' - through the Dead Marshes, outside Mordor - again walking on a boardwalk.  Gollum says, don't follow the lights.

Just a gentle reminder.  Some of the other warning signs elaborate further on gruesome ways that you'll be injured if you step off of the boardwalk.

And there they are, all of a sudden.  Pine trees, then bam!  Boiling pots of mud.

There is also a nearby geyser, to which the boardwalk will take you.  The yellow around it are sulfur deposits.