Really enjoyed the Kim Stanley Robinson novela Green Mars. This is not Green Mars, the second novel in the Mars Trilogy, but a different story, written before but seemingly set in the same timeline. Recommend it very highly.
A short summary: Roger Clayborne (no relation) joins a small group in a climbing expedition up the 7km cliff surrounding Olympus Mons. As they climb up out of the atmosphere, Roger contemplates the meaning of his 300-year life.
