Heat the cinnamon, water, and sugar in a small pot over medium high heat.
Bring to a boil then reduce heat to medium low and simmer for 15 minutes.
Remove from heat and let the cinnamon sit in the syrup to infuse, at least one hour.
Store the syrup in a container, with the cinnamons sticks if desired. Keep the syrup refrigerated up to two weeks.
This makes between 1 to 1 1/4 cups of simple syrup per batch. If your cinnamon is older than 6 months, you may want to increase the infusion time or slightly increase the amount of cinnamon you use to make up for the weakened spice.