saguaro national park.
It's hard to really appreciate how big these guys are without something to give them scale. My husband (standing next to it looking up) is 5'9". Just as impressive is how much these things can weigh.
Fun facts: A 10 year old plant might only be 1.5 inches tall. Saguaro can grow to be between 40-60 feet tall (12-18m). When rain is plentiful and the saguaro is fully hydrated it can weigh between 3200-4800 pounds.