A MetroCard is not valid for use on PATH trains. PATH operates its own ticketing system, so riders will need to purchase PATH-specific tickets or use a PATH SmartLink card, which is a reloadable card designed for frequent travelers on the system. Tickets can be purchased at vending machines located in PATH stations, and fare information can be found on their official website. It is important for travelers to be aware of the convenience offered by the SmartLink card, especially for those who use PATH services regularly. This card allows users to reload funds easily, saving time and effort at the ticket machines. To ensure you have the most accurate and up-to-date information regarding PATH fare options, it is recommended to visit their website.