An imperial era Roman bath for one.
Note the hole in the bottom for the water to drain out, which presumably could have been plugged for the occupant to soak. A slave or servant would likely have poured the warmed water from jugs in through the large aperture at the top, which I suppose could have been done either while the occupant was in it or before they stepped in. Most bathing was done in public in this period, at large baths, though many rich houses would have their own smaller versions for the private use of the owner, his family and his friends. The rich would also often frequent the public baths even if they had their own, as it was a place for socialising and doing business as well as ablutions. This is the first single-person sized bath that I have seen however.
I've not got a date for this one, other than it's imperial, but I can tell you that it currently resides in the museum for ancient Cosa, which is on the site of the ancient city, in the modern small town of Andeselma, Italy. It's made from terracotta, and has obviously been reconstructed from fragments.