Catching a train in Munich

Follow the signs to the airport train station. There are overhead directional signs by the luggage carousels (see photo below), a train icon and/or a white "S" inside a green circle (universal German icon for S-bahn). Assuming you start after 9 am. Get a Bayern ticket out of a ticket machine for 31 EUR for 2 people. Pay an extra 2 EUR to buy from the ticket window. Take the S-8 train, which goes every 20 minutes and get off at Munich Ostbahnhof and change to the hourly Meridian train to Salzburg. It will be on a different track, so you will need to take the stairs down to the crossover tunnel to get to the right track. It might be a fast change depending on what time you take the S-bahn. If you mess up and take the S-1 which runs at times between the S-8 departures, fear not, it eventually gets to Ostbahnhof after stopping at the main station. Only use the Meridian trains. Your ticket is not valid on Railjet or EC trains.

Photo from the luggage carousels. Zoom in to see the direction sign on the right.
https://www.google.com/maps/@48.3530253,11.7862242,3a,37.5y,103.54h,90t/data=!3m8!1e1!3m6!1sAF1QipNWTdgl9q8kWme3bRCDYoE9lEB4jAk0P2MHV-Sy!2e10!3e11!6shttps:%2F%2Flh5.googleusercontent.com%2Fp%2FAF1QipNWTdgl9q8kWme3bRCDYoE9lEB4jAk0P2MHV-Sy%3Dw203-h100-k-no-pi-0-ya110.92156-ro0-fo100!7i8704!8i4352

The S8 goes directly to Ostbahnhof, before it goes through town to the Hbf and stations beyond to the west. In between S8 times, the S1 goes to the Hbf, then through town to the Ostbahnhof. The S1 will get you to the Ostbahnhof eventually, but the S8 get you there with the best chance of catching the next train to Salzburg.

And, by the way, don't let the destinations fool you. The S1 will show a destination of Ostbahnhof, because that is where it ends its route, but don't take it. The S8 will show a destination of Herrsching, Weßling, or ?, because it goes there eventually, but it goes to Ostbahnhof early in it's run.

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