Dress code is dependent on individual establishments, some casual, others keen on sophistication. Places of worship specifically do require you to dress modestly while visiting.
Bad language, loud behavior, and encroaching on other people’s boundaries are considered disrespectful. Respectful public decorum is always advised.
Certain shops close briefly during prayer times to allow time for worship. During the holy month of Ramadan, the rhythm of the country changes into a mellow, spiritual one.
The sale, purchase, and consumption of alcohol and drugs is illegal in Saudi Arabia.