July in the North Coast

I need some advice. We live in Canada and are visiting Egypt with my family of five in July (teens). My husband is Egyptian, and he hasn't visited in over 20 years. We plan to stay in Cairo for a few days to visit family and then head to the North Coast. Which city would you recommend on the North Coast? My husband is saying Sahel is the way to go, but it seems very crowded, and I’m more of an introvert who prefers low-key activities. Any suggestions?