This is an architectural gem - and a nightmare to sketch. Forgot to mention it is in Rio ...
In the first one, I started with the cylinder and the dome, then worked my way from there to the sides. I used Pentel Hybrid Technica 0.3. I bought a set of 4 to try out. I am always short of black pens. I like the line, it flows smoothly. I think they will be my main sketching tool in Brazil.
The second one was just brush - this would be the fastest way to capture something. I wanted to see how much - or how little - information that meant.
In the last one, I applied the analytical sketching method - I started with the big shapes: the box for the left side of the building, the cylinder of the front dome, the box connecting these two parts, the box for the right side of the building.Then I started adding details.