The S1 is a railway service of the Vienna S-Bahn that operates between Marchegg and Wien Meidling.

On 31 May 1959, the northern railway bridge was reopened allowing rail traffic from Floridsdorf to enter the city to Praterstern.

A big ceremony was held at South station as the inaugural train departed to Gänserndorf.

Austrian president Adolf Schärf, Vice Chancellor Bruno Pittermann, Mayor Franz Jonas, ÖBB president Maximilian Schantl and Transport Minister Karl Waldbrunner took part in the ceremony along with over 900 invited guests.

Many trains were overcrowded through the city center paving way for an agreement with VOR, the regional public transport company, allowing passengers to use city trams and S-Bahn trains with the same ticket.