Is it permissible to go to summer resorts if one is able to lower their gaze and keep away from forbidden things?

There is no impediment to a person enjoying recreation with themselves and their family, provided they adhere to the limits set by Allah. This includes the prohibition of intermingling between men and women in an atmosphere of immodesty, vulgarity, and gazing at 'awrah (private parts), as is common in mixed resorts. Being present in such places is forbidden, even with lowering one's gaze, because they are a place where Allah's wrath and displeasure descend, due to the display of adornment (tabarruj) and indecencies within them. Allah Almighty said: "And abide in your houses and do not display yourselves as [was] the display of the former times of ignorance."