Squeeze, if you live in Missouri you are in luck. They have just annexed (or in the process) the Rock Island rail line for another gravel route across Missouri . You can ride the Katy out then the Rock Island back. Right now it is rough. I haven't been on it but have seen pictures of others riding sections with their Moutain bikes. It probably isn't continuous yet but lots of it is ridable. ( sorry, I don't have a link.... Google it).