We stopped at the Giftun Island as part of our snorkeling trip. Although the water around the island is beautiful and clear the snorkeling itself is nothing special especially if you have already experience in snorkeling and/ or diving. Furthermore, this island is frequently visited by every travel agency around Hurghada so it will be crowded and completely overrun with other tourist groups (which will bring trash and noise to those surroundings). Additionally, I can confirm other reviews that you will not find any shaded areas so be prepared with sunscreen/ umbrella. Furthermore, bring some additional water because purchasing some might be either expensive or not possible at all.
Most of time this stop will be included in your snorkeling trip anyway, so if you don't mind this mass tourism and the feeling of being in an over-crowded swimming-pool you might enjoy the stay.
Otherwise, I would not recommend planning a trip solely to visit Giftun Island.
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