Is it permissible for a wife to refuse to go with her husband to a beach city for vacation due to the evils she perceives there, or must she obey him?

It is permissible to stroll in beaches and gardens as long as it does not lead to committing a sin or witnessing an abomination that cannot be changed. If going to the city results in impermissible mixing, then the wife is not obliged to obey her husband in going there, because the Prophet, peace and blessings be upon him, said: "Obedience is only in what is good." However, if no impermissible act results from it, then do not disobey your husband.