Across the Río de la Plata

If your route runs through Buenos Aires, the ferry across the Río de la Plata — the wide estuary Montevideo sits on — is the gentlest way into Uruguay with a bike. The boats leave from Puerto Madero, in the city, and two companies are the ones that matter: Buquebús, the larger, and Colonia Express, smaller and built around the Colonia crossing.

There are really three ways across. A fast direct boat runs Buenos Aires to Montevideo in a little over two hours. A shorter hop crosses to Colonia del Sacramento, the colonial town on the Uruguayan bank, in about an hour. And the most popular option for the money pairs them: the boat to Colonia, then a connecting coach on to Montevideo, on a single ticket. Schedules and prices are easy to compare on each company's site; what's worth settling in advance is how they handle the bike and the border.

Both companies carry a bicycle, the usual arrangement being one bike per passenger, stowed in the vehicle hold with the cars. Travellers report that Colonia Express asks for a signed waiver at check-in, and may want a wheel off if the hold is full. Buquebús carries bikes too, though the detail lives more in travellers' accounts than on the official page, so confirm it at check-in, especially in summer. Carry your panniers up to the passenger deck with you: the hold isn't reachable mid-crossing.

The border is the easy part, and the reason the ferry feels so calm: both countries' immigration and customs are done at the Puerto Madero terminal, before you board, so you step off already cleared. Leave a little extra time at check-in with the bike — and on the way back into Argentina, the customs service may fasten a seal to the frame; the seat tube is the tidy place to tie it.