Being English, I would dress as if going for a job interview, as first impressions count. Shirts - Trousers and Shoes. You have not said if this is for yourself or a lady whichever way, the same applies.
When I was there recently, I wore long pants, shoes and a nice shirt. My friend wore shorts, slippers and a t shirt. We both were welcomed in.
Better safe than sorry to no admittance. Wear long pants, collar shirt and closed shoes for the male, skirt, dress or pants and closed shoes for the female. Or go casual and take a change of clothes and sandals along. Have a safe trip.
