Walking down from the Prague Castle to Charles Bridge through picturesque narrow cobbled streets one comes across a narrow path between ancient buildings with the board Vinarna Certovka leading down a flight of steps to the river bank . This is the narrowest street in Prague - just possible for people to walk in a single file ( I am not sure if a heavy built person would be able to walk through) and has now become a major tourist attraction.
The path leads to terraces above the banks of the river Vtlava with restaurants overlooking the river and Charles Bridge. The buildings date back to the 14th and 15th century,
Note the traffic light has been fixed on both ends enable trouble free passage. Do make a point to walk down the street even if you feel that you wont be fit into the narrow path. The street where this is located - U Lužického semináre no. 24.
Thanks & Best Regards,