I was at early check out at the Hyatt in Mendoza when I checked the weather report. It had snowed overnight in the Andes and the pass to Chile was temporarily closed. Our guide appeared to be unworrried, but a snow delay could screw up the timing for the next few days.
Four Hour Drive to the Chilean Border
It is a four hour drive from Mendoza to the tunnel that marks the 11,500 foot border between Argentina and Chile, usually plenty of time for the snow to be cleared from the tunnel entrances.
The drive is spectacular. It was fall in the Andes and the most visible color was the orange yellow of the tall Lombardy poplars along the roadside.

It Snowed Overnight
The snow on the mountain tops set off the roadside trees. It looked like this for miles. This drive is one of the best parts of the trip – much better than flying from Mendoza to Santiago.

Alongside the Highway to Chile
Mount Aconcagua
There were no memorably steep hills on the way to the border, just a steady climb for mile after mile. But we knew we were getting up there. We had a couple of climbers in our group, along with our guide who pointed out Mount Aconcagua in the distance. At 22, 500 feet plus, it is the highest mountain outside of Asia.

Mt Acongogua behind the clouds
Crossing the Border
The border crossing between Argentina and Chile is not exactly like going between the US and Canada. Chile is very fussy about any possible agricultural pests. They have no hoof and mouth disease, mad cow disease, med flies, grape destroying phylloxera, etc. and want to keep it that way. With the Pacific on the South and West, a big desert in the north, and the Andes in the East, they are effectively isolated and take advantage of this to inspect whatever crosses the border, slowly. We had to give up a couple of sandwiches which were smoked meat, therefore suspect and gone.

High Altitude Border
The Quick Route Down
The highway on the Argentinean side is scenic. About half of us kept our eyes focused on the floor of the coach on the way down into Chile. 32 switchbacks made the drive one that we wont forget quickly. And this is the section that they closed because of snow.

32 Switchbacks to Chile
At this time of year most of the traffic is professional drivers, buses, trucks and the like. We hear that this and the border crossing can get really bogged down in the summer months when there is no snow and lots of tourist traffic.