Niko's Greek Kitchen is located inside the West Street Market on West Street between 1st and 2nd Streets. Niko's Greek Kitchen has occupied this space since West Street Market opened, and brings in a steady stream of regulars.
Street parking can be iffy, especially during special events downtown. I would suggest using the City's parking garage, and the entrance to that garage is located on First Street. Niko's will validate your parking ticket so parking is free.
Niko's Greek Kitchen is located INSIDE West Street Market (you can't see it from the street). You can't miss its interior blue facade.
Now for the food: The gyro meat is done properly on the vertical spit, and the pita was soft. The tzatziki was the perfect yogurt, cucumber, and dill blend. The food is prepared right in front of you, so there are no surprises. They also have one of the most unique chicken caesar salads I've ever encountered, with seasoned flat chicken strips rather than the traditional chopped chicken found in a caesar salad.
The dining atmosphere is near-perfect, sharing an open dining space with the other tenants in West Street Market. It's not uncommon to find artists, geeks, families, business folks and downtown residents congregating in the old warehouse-style refurbished building.
I definitely recommend Niko's Greek Kitchen for lunch.