I drive from Elizabeth to Golden in about an hour... barring any accidents. Ben Lomond site is about 20 minutes from Elizabeth... soooo count on at least an hour and ten from Denver. It is a beautiful drive, this high-plains Elbert County. You will like the drive.
PS... Do the speed limit [30Mph] through Elizabeth and Kiowa!!!!!!!!!! They do need your money!!!
PSS. PM me for the Elbert County Sheriff's channel frequency - if you have a scanner.