More than 500 years old, Phnom Penh is rich in culture, history and style! Sightseeing spots include the Royal Palace and the National Museum displaying Cambodia Monarchs' history, galleries featuring ancient artifacts of Cambodia's rich culture. The Royal Palace is open to the public everyday, except when the venue is needed for ceremonies, in which case some parts of the palace may be closed and unaccessible. Beside the Royal Place, the whole riverside area transforms into a dynamic city centerat night. To experience the dark past of the Khmer Rouge era, stop by the Tuol Sleng genocide museum and the killing fields on the outskirt of the city. The Genocide museum is usually open everyday. Formerly known as S-21, the Genocide museum is home to horror and sadness, a gloomy atmosphere still haunts the premice. Tourists often report being affected by the ghosts of the horrendous events which took place there. Recollections of last days of hundreads of prisoners are exhibited, picturing the torture machinesand tools, as well as pictures of countless bodies are found inside each building.