Like "cymro", I have spent time along the southwest border areas in California, Nevada, and Arizona
the last few years during the winter months. I have driven up to and through several inland Border
Guard checkpoints while driving with BC Canadian plates. They asked a few general questions but
never asked to see my passport or driver's licence. They were always polite. I have been stopped
twice by Border Patrol trucks. Once while riding south of Tucson on hwy 82, and once when riding
on 85 south of Why. They also just asked what I was doing, where I came from, and where I was
headed. Because I had minimum gear, basically just water, tool kit, camera, map, lunch, and no tan,
they knew I was a Canadian Snowbird.