Fortifications. Cities at this time were great walled-in islands existing in the midst of fields and pastures. A traveler approaching the early-modern city encountered on either side of the road, cows, sheep, and goats grazing in the pastures lying outside the city's walls. Most cities of Europe were encircled by constantly repaired Roman and Medieval walls, and often by moats filled with flowing water, as well. Gallows and torture wheels (heavy wooden wheels used to crush a convict's bones, and then attached— with the still-living victim twisted among its spokes — to a huge pole) dotted the landscape outside the walls. The rotted corpses of those executed were left deliberately outside the walls to prevent disease and to serve as a warning to newcomers that the city's laws were to be obeyed.

City Gates. Due to the almost constant warfare of the...