Dromedary

A couple of times a week I ride here with my bike. But it is the first time I saw this. Thanks to Blip!
3 Dromedaries walking on the railroad.
Back home I searched the internet to find out about these dromedaries.
It is an artwork from Iris Le Rütte, called "Fata Morgana".
Three dromedaries walking quietly on the railway bridge over the Ringdijk. They all run parallel to the flow of traffic on the Wibautstraat as on the railway track.
They move like three dark silhouettes along the horizon to the east. The dromedaries, walking in the desolate desert of stones in the urban landscape. Are these "ships of the desert" a mirage or are they real?