The varied relief as an amphitheatre consists equaly in mountains, hills and plains.
The capital city is Ploiesti, with its about 300,000 inhabitants, situated 60 km North far from Bucharest and 40 km far from Otopeni international airport.
Dated back from 1503, Ploiesti was named a town in 1601 by Voivode Mihai Viteazu, when the first Union of the Three Romanian Lands was done. Ploiesti developed thanks to its geographic possition, and especially to its oil. The oil started to be rafined since 1857. It is the capital of all activities regarding the oil in Romania and one of the most important centres of drilling and petrochemical technology in the world. All these can be found in the Oil Museum. The Holology Museum is also a place of tourist attraction.
The tourism is a main activity in this county. Being named the most wonderful region of the Carpathians, the Prahova Valley willi its resorts (Sinaia, Azuga, Busteni, Breaza) is an interesting region both for tourists and investors. Also, the Teleajen Valley and the Slanic Valley, with their known resorts ( Valenii de Munte, Cheia, Slanic) complete the tourist potential of this county. Each resort is very characteristic and has accomodation and curing facilities. This county has 11, 681 places in 22 modern hotels, eight motels, 14 pension-hotels, 19 peasant houses and 159 villas, being able to accomodate over 620,000 tourists yearly.
Sinaia, "the Fine Pearls of Carpathians", is 1,000 m above sea level. The main point of interest is the Pelts Castle, built at the end of the XIX-th century in a Germanic Style. It has 160 rooms and valuable collections of art, arms and furniture. The Sinaia Monastery, built in 1695-1796 in a Brancoveanu's style is a valuable museum of manuscripts and art.
Busteni resort is situated on the Prahova Valley, 135 km far from Bucharest, between the Caraiman (2284 m above sea level) and Cosila (2489 m above sea level) Peaks.
Azuga, situated on the national road 15 km far from Busteni, is known since the XIII-th century as a spa with mineral waters.
Valenii de Munte is situated on the Teleajen Valley and surrounded by hills covered by forests and pastures. It is known thanks to the "Nicolae Iorga" Summer University which gathers scientists from Romanian and abroad.
Slanic, situated on the Slanic Valley, 400 m above sea level, is known for the therapy with aerosols and heliotherapy inside the salt mine which is one of the biggest in Europe. Other interesting places are: the Salt Mountain (100 m in high, natural reservation), the Salt Drift (14 km long and unique as to its configuration), the Piatra Verde Peak, 4 km far from the town and offering a wonderful landscape.