As if Peru doesn't have enough awesome stuff to see, they added a few more tentative places in 2019. I'm quite sure most were already on the average tourist's itinerary. Take a bus from Cuzco towards Urubama and drop off at the junction heading to Maras to find a taxi driver who will take you around. If not then take a bus that heads to Maras and ask around in the "town". The junction has a shaded bus stop to wait for buses heading back. I ended up taking a bus that goes the "scenic" route through the villages which cost me nothing but pain, literally, it was almost a penny to take the bus but the road is bumpy and dusty and the "air-con" aka "windows are open" doesn't make it pleasant - you do get to meet some interesting characters though. Also the buses on the main road are often full so I was happy to get going one way or the other.
Anyhow, the region is super popular with tourists already and this was a day trip together with Moray which is ultimately a great day out but nothing I would see on the UNESCO list as outstanding value. The same salt mine structures are in northern Spain, and...well, other places. I think they do it better in Spain anyway. It also takes an effort to press through all the tourist crowds that shop on the only way down the ramps and most of it wasn't even salt-related. I overheard a guide talking about the process of several drying layers which wasn't the case in the Spanish site but perhaps it is the same...
The only thing I thought was worth seeing is that the mountains in the area make it a great sight. As there are many other things to see in the area it isn't even a long detour just for the view so don't forget to add this to your trip - it only takes 20-30 minutes to see everything really.