I visited this WHS in June 2017. Having read the previous reviews I didn't have high expectations. I agree that a visit to the National Museum in Ashgabat is essential to understand the importance of this Partian site and it is relatively easy to combine such a visit as the site of Nisa is very close to modern Ashgabat.

The view from the platform next to the entrance (top right photo) is the most 'iconic' view you'll get even though the view from on top of the partially excavated mud brick walls with the surrounding mountain landscape is not bad either (bottom left photo). Like in the Ancient Merv archaeological site, while walking through the maze of mud brick walls and pillar remains, it's easy to observe the now exposed repellent materials used during the site's construction against insects (mostly termites and wasps) and birds.

Same as in Merv and Gonur Tepe, there are several old clay fragments still scattered everywhere on the floor. There's a small room where a few important remains and fragments from the building's coloured friezes could be seen but it's more of a storage room raher than a visitor centre proper. The most important artefacts can be seen in the National Museum in Ashgabat. The highlights were the dozens of beautiful ivory rhytons (bottom right photo) and the head of a clay statue with traces of colour painting (top left photo).

More coloured paintings are still buried under the mud and have not been excavated yet but part of a coloured frieze can be seen on ground level in what is known as the round/oval room. The remains of New Nisa are even less spectacular as only the foundations of residential areas remain. When there wasn't much to see, I just sat down and enjoyed birdwatching in the scenic natural surroundings (mostly falcons, owlets, rollers, bee-eaters, warblers and wheatears).

All in all I think that its OUV lies in the fact that it is one of the last remaining Partian sites but other than that don't expect to see much.