Crossing the Border Between Chile & Argentina
The border between Chile and Argentina is still strictly maintained, but crossing it doesn't present much difficulty beyond getting out your passport and waiting in a line to get the stamp. Most travelers end up crossing the border by bus, which means getting out of the vehicle for 30–45 minutes to go through the bureaucratic proceedings, then loading back in.
Crossing by car is also quite manageable (check with your car-rental company for restrictions on international travel). Chilean customs officers are extremely strict about bringing food into the country, especially compared with their Argentinean counterparts. Always declare food products (they are usually flexible once items are declared); otherwise, you face a hefty fine.