My question is why is benzene less reactive than 1,3,5-cyclohexatriene?

I know that benzene does not undergo addition reactions and is extremely stable to oxidizing reagents. C atoms in benzene are connected by delocalized double bonds which make them available to all carbon atoms at the same time. This makes the ring system unusually stable.
I cannot find anything on 1,3,5-cyclohexane and why it is more reactive.