After visiting the Palace Bidha next door, it is a short walk here. There are guides and you may want to hire one for a through explanation of these tombs.
It takes about 1 hour to see everything here and the final tombs at the end will have a long line, but it is worth it.
Make sure to see the video on how the construct the tiles, oddly it is in Spanish in a country that speaks Arabic & French?
This is a must see site in Marrakech