However, get medical help right away if you notice any symptoms of a serious allergic reaction, including: rash, itching/swelling (especially of the face/tongue/throat), severe dizziness, trouble breathing, kidney problems (such as change in the amount of urine). This is not a complete list of possible side effects.
They are more active when it is cooler, but they can and do come out of hiding at any time of the day. Here in the desert, Arizona Rattlesnakes can easily overheat and die if they cannot find a cool place to keep themselves cool.
In 1862, the California Column drove the Confederate forces out of Arizona. Tucson and all of what is now Arizona were part of New Mexico Territory until 1863, when they became part of the new Arizona Territory. From 1867 to 1877, Tucson was the capital of the Arizona Territory. Tucson was incorporated in 1877, making it the oldest incorporated city in Arizona.