Hotel Clementin is situated in the heart of the historical centre of Prague, between famous Charles Bridge and Old town square. Rarity is the minimum width of the house (3.28 m), making it the narrowest preserved house in Prague. Building history of this house is uncertain, lay-out of the city, however, shows that the house was developed by a supplementary division of a larger neighbouring building.House No. 176/4 At the Virgin Mary from the year of around 1360 (later also called At Our Nice Lady) is a very narrow ( 3.28 m!), biaxial, three-storey house, set in a crooked Semináøská street – this irregularity shows a very old origin of the street and houses located there.Building history of this house is uncertain, lay-out of the city, however, shows that the house was developed by a supplementary division of a larger neighbouring building. Current look of the exterior and interior is a result of modern modification of late classicist facade. The oldest part of the house is a Gothic cellar with an unusual massive wall, where also a part of a stony, certainly medieval vault, remained preserved. Until 1433 the house was obviously part of the neigbouring house No.175, whose part was probably the cellar space. It is not possible to exclude that in the 16th century frontal part to Semináøská street was built up, where there was probably a narrow street between the houses. After following connection with number 175 in 1627 the house had the same facade. Renaissance construction corresponds with an overlapping floor over the ground floor. Probably in the 17th or at the beginning of the 18th Century, the house became totally independent. At that time the house was increased by a 3rd floor. The entry into the house is framed by the sand-stone Baroque ribbon portal with a transom light.