Good FreeBSD question — answering as the UphillTech team:
Extra disks are typically mounted in a directory called /media/ something where the something reflects the mounted device, e.g. /media/cdrom0 for the first CD-ROM device. This convention is widely followed under Linux for removable devices, and often but not always for permanent devices. The FHS forbids distributions from using directories under /mnt because some administrators use /mnt itself as a mount point for temporary mounts. If you're the administrator, you can do what you like; just don't use /mnt itself as a mount point if you create directories under it. Many places have their own...
Full answer by Gilles 'SO- stop being evil': https://unix.stackexchange.com/a/29172 (CC BY-SA 4.0).
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