Pskov is exceedingly rich in tiny, squat, picturesque churches, dating mainly from the 15th and the 16th centuries. There are many dozens of them, the most notable being St. Basil's on the Hill (1413), St. Kozma and Demian's near the Bridge (1463), St. George's from the Downhill (1494), Assumption from the Ferryside (1444, 1521), and St. Nicholas' from Usokha (1536). The 17th-century residential architecture is represented by merchant mansions, such as the Salt House, the Pogankin Palace, and the Trubinsky mansion.