Sourcing old railroad ties?

When I lived in Cedar Falls, they had a railroad tie graveyard for people to dump them, in some remote ass spot out in the sticks, I’m assuming because they can’t be mulched or burned due to the nasty chemicals. They were also free for the taking on the rare occasions anyone needed some.

It’s now a rare occasion that I myself need a few. Does Iowa City have a place like this? Looking at the landfill website doesn’t lend any info. I’m hoping someone in the landscaping industry locally can maybe chime in or help me source a few old ties.

Thanks!