I did this as a day trip in 2010, took a local bus leaving from Posadas which crosses the bridge into Encarnación. Bus stops on the bridge for immigration for both countries. Check your visa requirements because AUS, NZ, US citizens need prior visa first. Spent the day looking around the markets which are quite cool, and had a very nice and cheap lunch, found the bus coming back and arrived back in Posadas.
All very quick and easy. If you don't have a prior visa (as I didn't), the customs guys will ask for some money for a "day pass" if your just going to Encarnación.. however if your planning to be there for a few days/weeks then this trick doesn't work.Edited: 28 September 2012, 15:37
-:- Message from TripAdvisor staff -:-
This topic has been closed to new posts due to inactivity. We hope you'll join the conversation by posting to an open topic or starting a new one.
To review the TripAdvisor Forums Posting Guidelines, please follow this link: http://www.tripadvisor.com/pages/forums_posting_guidelines.html
We remove posts that do not follow our posting guidelines, and we reserve the right to remove any post for any reason.