You are extremely close to the old city...probably a 5-7 minute walk before the shops and restaurants actually start (or less). Although some of the streets are cobblestone, not all of them are...nor the sidewalks so you should be fine for walking. If staying at the Marriott...if you exist the hotel on the side that has the courtyard...the street right in front of you brings you right into the old city. Ask the Concierge if you are unsure...the staff at the Marriott are very helpful. If you want to visit the Citadel which I strongly recommend...that walk will be a bit longer and a bit uphill...but the view of the city and surrounding area once on the hill will be worth the effort! It is truly a beautiful city and lots of great restaurants as well.