The eastern part of the province contains the flat river plains of the Mae Klong, crisscrossed by many khlongs.

Some caves are inhabited by large colonies of bats, and it is an impressive sight when they swarm out in the evening to feed.

The city of Ratchburi is on the banks of the Mae Klong River and was a town of the Suvarnabhumi Kingdom.

From the evidence of archaeological sites and many antiquities, believed that people have settled in this area since the Middle Stone Age, as well as discovering an ancient city in the Dvaravati period at Mueang Ratchaburi district.

Especially during the reign of King Rama I has brought troops to set up the Burmese battle in Ratchaburi area many times, the most important one was the Burmese–Siamese War (1785–1786).

Later in 1817, In the reign of King Rama II has ordered to build a new city wall on the left bank of the Mae Klong River until the present.

In the reign of King Rama V in 1894, has changed the government and included the city that are close together to set up as counties and included the city of Ratchaburi, Kanchanaburi, Samut Songkhram, Phetchaburi, Pran Buri and Prachuap Khiri Khan to set up as Ratchaburi county.

Hill tribes, mostly Karen living near the Myanmar border, make up about one percent of the population.

[13] Jullien's golden carp (Probarbus jullieni) is the provincial fish, same as neighbouring province Kanchanaburi, that has good taste and flourished in the Mae Klong River in the past, but is now critically endangered.

As of 26 November 2019 there are:[16] one Ratchaburi Provincial Administration Organisation (ongkan borihan suan changwat) and 34 municipal (thesaban) areas in the province.

Ratchaburi, Ban Pong, Tha Pha and Photharam have town (thesaban mueang) status.

The non-municipal areas are administered by 77 Subdistrict Administrative Organisations - SAO (ongkan borihan suan tambon).