Train Info
You will want to use the ‘local trains’ station at the airport. This is located directly below the terminal 1 to 2 shuttle bus station. It is at the foot of the tall escalator. Look for this symbol:

This will take you below ground level. Find a kiosk that looks like this one (RMV) and purchase your ticket to Mainz Hbf. If you are staying in Mainz overnight, you do not need a return ticket.

You will want to take the S8 train in the direction of Wiesbaden-Hbf. You will get off at Mainz Hbf. (it is the eighth stop from the airport).
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