I remember this took me a little longer to draw as there was distraction from the conversations, tourists, movements around me at this manificient building. About 30 minutes. When I was to add the details to the cupola, it was about 4pm in the afternoon and the sun light was already moving upward so I had to make some 'adjustments'. This had resulted in a darker shades on top. Hmmmm, go ahead if you want to call it a mistake! HA!