I was expecting the four-day walk across the Chihuaha desert to El Paso to be an ordeal, and it was, but not in the way I'd expected. The big problem was the wind.
It started as I made the steep, 6,000-foot ascent of the Guadalupe mountains south of Carlsbad. Normally the stroller just rolls quietly and uncomplainingly along, and I hardly notice it's there. But with a powerful desert wind blowing in my face, and laden with four days' food and eleven litres of water, pushing it uphill was a Sisyphean task. I had to keep pausing for breath, and my pace slowed to a crawl.
At the summit, I dropped in on the Guadalupe mountains visitor centre, a haven of clean restrooms and piped classical music amid the wilderness. They had a little weather station, and I asked what the peak gust had been in the past twenty-four hours. They told me it was eighty miles an hour, which is hurricane force.
It went on like that for the next four days. It's still blowing here in El Paso, though not nearly so hard, and it will probably be a problem all the way across New Mexico and Arizona. As a result, instead of being pleasantly tired as I am at the end of most days, I was exhausted and dehydrated.
On the plus side, while this has been the most challenging section of the walk, it's also been easily the most spectacular: stark mountain outcrops, cactus-studded dunes, soft brown grass rippling like an ocean.
It's also been the most solitary few days since I started my walk. Drivers tend to set the cruise control at the 75-mph speed limit, surprisingly generous for a narrow two-lane road, and go into a trance - as witness the many sad little crosses heaped with plastic flowers I saw along the way, commemorating people who presumably fell asleep at the wheel.
Usually, I get a steady trickle of people stopping to chat and offer me rides, and this helps me to get through the day. But there were none this time, so I had to put my brain in the equivalent of cruise control and walk as long and as hard as I could to get it over and done with. Yesterday I covered thirty-two miles, which is a record for me.
I last came to El Paso in 1978, when it was a dusty border town, home to 600,000 people; today it's a huge sprawl with more than twice the population and some of the most high-density housing I've ever seen in this country.
El Paso and its sister town of Juarez in Mexico are really just one big conglomeration: two worlds separated by a fence, a bit like pre-1989 Berlin. I'm hoping to go and have a look at Juarez tomorrow.