There is a fun play called “You can’t take it with you”. The opposite is true on your bicycle: you can take things. Some rides require taking lots of stuff. Most first time touring cyclists take too much. On my first major tour, I mailed a box home after the first week. My planning was good, but on the road I found some things to be extraneous.
There are a few things I consider mandatory on any ride longer than going to a store. There are a few others things I take on longer rides. So here goes, unzip that expander portion of your seat bag and consider taking it with you.
On Longer Rides: