Alfândega do Porto, 'the old customshouses', an iconic site of cultural significance dating back to the year 1335 that has grown and developed with Portugal's expansion of trade, and the location of the 2024 Concordia Europe Summit's closing reception. Guests will be transported through the wine region by boat across the Douro River, an essential route of trade and communications for the Iberian Peninsula – responsible for making the Douro Valley one of the oldest urban centers in Europe.