Terme Dobrna is the oldest working Slovenian thermal spa with a tradition over 600 years old. A mild climate that does not know fogs or cold winds had attracted early on the first settlers. In prehistoric times, they erected a fortified settlement on the nearby hillock Gradišče, testimony of early settlement are also 500 Celtic coins found in archaeological excavations.
The findings also prove that Dobrna was well known by ancient Romans. It is likely that already then they started using the thermal waters of Dobrna. The thermal spring was known as well by first Slovenian settlers as they named the upper part of their settlement ‘Toplice’ meaning ‘Spa’. The lower part of the settlement they named ‘Dobrna’ after the ‘dob’ an oak tree characteristic to the widely surrounding area. The Dobrna spa and thermal spring are first mentioned in written records in the year 1403. At that time, they became the property of Sigmund and Andrej Dobrnski.