Duty-free shops and stalls lining the Interamericana announce the approach to PASO CANOAS . As you come into town, either driving or on the TRACOPA or international Ticabus service, you'll pass the Costa Rican customs checkpoint, where everybody gets a going-over. Foreigners don't attract much interest, however; customs officials are far more concerned with nabbing Ticos coming back over the border with unauthorized amounts of cheap consumer goods.

To cross from Costa Rica into Panamá, most nationalities need a tourist card : though UK citizens need only bring their passport. Tourist cards should be collected in advance from the Panamanian consulate , or from the office of Copa, Panama's national airline, in San José. Many people should also have a visa - Canadians, Australians and New Zealanders among them. You may also need a return ticket back to Costa Rica or an onward ticket out of Panamá to another country (though the cheapest TRACOPA fare will do), but bear in mind that immigration requirements frequently change, seemingly at whim, so always check with the Panamanian consulate before setting off.

The migración is on the Costa Rican side, next to the TRACOPA bus terminal. You'll have to wait in line, maybe for several hours, especially if a San José-David-Panamá City Ticabus comes through, as all international bus passengers are processed together. Arrive early to get through fastest. There's no problem changing money : there's a Banco Nacional on the Costa Rican side of the border and, beyond that, plenty of moneychangers. Note that you cannot take any fruit or vegetables across the border - even if they're for your lunch. They will be confiscated.

DAVID , the first city of any size in Panamá, is about ninety minutes beyond the border. Buses run from the Panamanian border bus terminal every hour or so until 5pm. From David it's easy to pick up local services, including the Ticabus to Panamá City, which you can't pick up at the border.