Has anyone experimented with the serial port on the Arduino Opta?

Question: has anyone experimented with the serial port on the Arduino Opta? On the Uno et al there are pins broken out as Rx and Tx, but I'm not sure the Opta has this functionality. One could probably do some sort of breakout with the USB-C port, but perhaps there is an easier way. I think it may have more than one serial port, available, but not certain.