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Just west of Petchburi's city center is a three peaked hill locally called Khao Wang, which translates to "Palace Hill". In the 1850s, King Rama IV (Mongkut) commissioned a summer palace to be built on the northern-most peak. Before he became king, Mongkut spent many years as a monk. During that time, he had spent many nights in the temple at the base of Khao Wang, Wat Maha Samanaram.
View of Khao Wang from Phra Ram Ratchaniwet Palace
The structures on the hills essentially comprise three groups: the palace complex on the northern-most peak, the Chomphet pagoda, and Wat Phra Kaeo Noi temple. There are several paths up to the hilltops, but you'll most likely use one of two routes: The easy way is to take the cable car on the western side of the hill. The car will take you to just below the palace complex. The cable car costs 40 Baht (1.04 USD) for adults, in addition to the park entrance fee.
The main alternative to the cable car is to walk up the wide pathway starting from the base of the hill on the east side, next to Wat Maha Samanaram. The walk is not difficult and there are several structures of the palace to stop and see along the way.
All of the buildings of the palace and its temples sit in the midst of a forest of frangipani trees that covers the entire hill. Making their home in the forest as well as the palace complex are several troupes of monkeys, pig-tailed macaques to be exact. Although not as aggressive as those at Lopburi, the monkeys can still be a nuisance. You need to be careful with your belongings.
The palace buildings are open daily from 9:00 am to 4:00 pm. Admission to the palace museum is 150 Baht (3.90 USD).