What episode in Rurouni Kenshin did the boys walk on girls a bath house?

You're likely thinking of the episode where Kenshin and Sanosuke inadvertently stumble into a women's bathhouse while chasing a thief. This happens in Episode 12 of the 1996 Rurouni Kenshin anime, titled "The Thief's Hideout."

It's a comical scene where Kenshin and Sanosuke get into a lot of trouble for their mistake, resulting in a hilarious encounter with the bathhouse patrons.