After early morning pickup from your Marmaris hotel, transfer to Dalaman Airport for your 1.25-hour flight to Istanbul.
When you arrive in Istanbul, meet your guide at the airport and head to the old town (Sultanahmet). Start by touring Topkapı Palace, the primary residence from 1465-1856 for the Ottoman Sultans. See the Imperial Treasury's collection including traditional clothing, jewelry, sacred Islamic relics from the Prophet Mohammed, and more.
Afterward, have one hour on your own to purchase lunch at a nearby cafe or restaurant, then head to Sultanahmet Square, aka the Hippodrome, which was used for official ceremonies by the ancient Romans of Constantinople. View monuments in the square such as the German Fountain of Wilhelm II, the Serpentine Column, and the Obelisk of Theodosius, then go to the nearby Blue Mosque, which is renowned for its fine interior lined with blue tile work.
Next, test your bargaining skills while browsing the jewellery, clothing, textiles, and other goods at the Egyptian (Spice) Bazaar. Then have the option to experience the Bosphorus River sightseeing cruise (additional expense) and see Istanbul from the waterway that runs between the European and Asian continents.
Eat dinner at a local restaurant (own expense) before transferring to the airport for your flight back to Marmaris where your tour ends with hotel drop-off.