The Short Answer: Yes, Easily
Visiting Ephesus independently from a cruise ship is straightforward, safe, and significantly cheaper than a ship-organized shore excursion. Thousands of cruise passengers do it every port day. The site is well-signed, the path through the ruins is logical, and you do not need a guide to appreciate what you are seeing—though a good one certainly adds depth.
Step-by-Step: DIY Ephesus From Kusadasi Port
Step 1: Walk through the port gate. Taxis line up just outside. Negotiate a fare to "Ephesus Upper Gate" (Efes Ust Giris). Expect 300-400 TL ($10-15). The drive is about 20 minutes.
Step 2: Buy your ticket at the Upper Gate. General admission is 750 TL (~$22). The Terrace Houses are an additional 500 TL and worth every lira. You can pay by card or cash (Turkish lira preferred, euros sometimes accepted at a poor rate).
Step 3: Walk downhill through the site. The main path from Upper Gate to Lower Gate is about 2 km. You will pass all the major landmarks: the Odeon, Domitian Temple, Hercules Gate, Curetes Street, Hadrian Temple, the Terrace Houses entrance, the Library of Celsus, the Commercial Agora, and the Great Theatre.
Step 4: Exit at the Lower Gate. Taxis wait here. Ride back to Kusadasi port (same price range), or walk 3 km into Selcuk for lunch and the Ephesus Museum.
Cost Comparison
Ship excursion: $80-120 per person (group of 30-45, fixed schedule, guided). Private guide + vehicle: $150-250 total for 2-4 people (flexible, personalized). DIY by taxi: ~$50-60 total for two people (taxi both ways + two entrance tickets + Terrace Houses). That is a saving of $100-180 per couple compared to the ship excursion.
What You Might Miss Without a Guide
A good guide brings the stones to life. They explain what the graffiti on the latrine walls says, why the Library of Celsus faces east, and how the brothel across the street from the library was connected by an underground tunnel (a fact that delights every tour group). If you go independently but want context, consider downloading an audio guide app or reading up beforehand.
Is It Safe?
Turkey is safe for tourists, and the Ephesus area is especially tourist-friendly. The route from port to site and back is well-traveled. Taxi drivers are used to cruise passengers. The main risk is not danger—it is running late and missing your ship. Set a firm return time and stick to it. Your ship will not wait.