What were the bath houses in ancient Rome?

Bath houses in Ancient Rome were common spaces where Romans could go to bathe and relax. They were open to all Roman citizens, but had a class structure rooted within them. Rome's higher elite class would have exclusive areas in which to bathe compared to regular citizens. The baths were additionally separated into men's and women's sections.
They were social spaces in which business deals would have occurred and other political affairs. Many have compared their use to golf courses, as they have multifaceted uses (relaxation, business, etc.).
The bath houses varied in size, but the largest served up to 3,000 bathers at a time. Rome's use of bath houses was adopted from the Greeks; who had built bathing facilities across the scope of their empire, some even being built in Alexandria, Egypt. Rome followed this custom and built bath houses throughout their own empire. This is why one can visit Bath, England; which is famous for the Roman baths that were built there during Roman rule.

Communal bathing in ancient Rome was a social, hygienic, and therapeutic ritual that was common among most strata of Roman society. The Romans inherited their penchant for communal bathing from the Greeks, who first prioritized this aspect of civic life. Bath houses, or facilities at which such group bathing occurred, could generally be divided into two types: balneae and thermae.
Balneae were small, utilitarian facilities existing in great quantity throughout the empire. The thermae, by contrast, were large, elaborate, state-maintained bath houses established in most Roman communities. These complexes included separate bathing areas for men and women, as well as changing rooms and gymnasiums. The largest recorded thermae, the Baths of Diocletian, could reportedly accommodate nearly 3,000 bathers. Other notable thermae included the Baths of Trajan and the Baths of Caracalla.
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