Tucked into a small building on Old Town's San Felipe Street, the American International Rattlesnake Museum houses the world's largest collection of live rattlesnake species in a public display — over 30 different species from across North and South America. The place is small, intimate, and genuinely educational rather than lurid. The snakes are kept in climate-controlled terrariums, and staff are knowledgeable about the ecological role rattlesnakes play in desert ecosystems.
The museum exists partly to correct the fear and misunderstanding that leads to unnecessary snake killings. The information about venom, bite treatment, and the actual (very low) risk to humans is presented without sensationalism. An unusual attraction, but a memorable one — you won't see a collection like this anywhere else. Entry is cheap. Allow 45 minutes.