You’ll have to make sure that the loop module is loaded before you can use this feature.
sudo modprobe loop
Mount a CD ISO Image
We’ll use the regular mount command to mount the ISO image into a folder, just like you would do with a regular drive. The difference is that we pass the -o loop command to specify the loop module, which can handle ISO images.
sudo mount filename.iso /media/iso -t iso9660 -o loop
Of course you should make sure that you have created the /media/iso folder ahead of time.
Mount a DVD ISO Image
When mounting ISO images of DVDs, you might have to use the UDF type instead of ISO.
sudo mount filename.iso /media/iso -t udf -o loop