Translation of nightmarish in German

We sat on the balcony and saw that the hotel had even a pool on the roof top but I did not have the courage to jump in. It just looked to dirty and as no one was in there I did not need to be the first.
The memorial consisted of a small museum and monument which was displaying skulls of civil war victims. It was sad, brutal and scary. It is certainly not the place were you would take tourist on day one.
The drive to these lagoons was not easy. The jeep did not have air conditioning, so that in the sun it would get extremely hot and in the shade extremely cold. The jeeps were around 15 years old.