Colorado expressly allows one to carry a concealed weapon (firearm) under the following circumstances (see C.R.S. sec. 18-12-105):
1) in his own dwelling or place of business, or on property under his control at the time of the act of carrying; or
2) in a private automobile or other private means of conveyance for lawful protection of his or another's person or property while traveling; or
3) when one is a permit holder;
4) when one is a peace officer; or
5) when one is a federal probation officer, or pre-trial services officer, within the scope of his duties.
Any other situation requires a CCW Permit.
You forgot:
6) Open Carry