A special interest attaches to Havana, as it is to be a city under the control of the United States.  The surface soil consists for the most part of a thin layer of red, yellow, or black earths.  At varying depths beneath this, often not exceeding 1 or 2 feet, lie the solid rocks.  These foundation rocks are, especially in the northern and more modern parts of the city toward the coast of the sea and not of the harbor, Quarternary, and especially Tertiary, formations, so permeable that liquids emptied into excavations are absorbed and disappear.

In other parts of the city the rocks are not permeable, and pools are formed.  In proportion as the towns of Cuba are old, the streets are narrow.  In Havana this peculiarity is so positive that pedestrians cannot pass on the sidewalks, nor vehicles on the streets.  Less than one-third of the population live on paved streets, and these are as well paved and kept as clean, it is believed cleaner, than is usual in the United States.  The remainder live on unpaved streets, which, for the most part, are very filthy.  Many of these, even in old and densely populated parts of the city, are no better than rough country roads, full of rocks, crevices, mud holes, and other irregularities, so that vehicles traverse them with difficulty at all times, and in the rainy season they are sometimes impassible for two months.  Rough, muddy, or both, these streets serve admirably as permanent receptacles for much decomposing animal and vegetable matter.  Finally, not less, probably more, than one-half the population of Havana live on streets which are constantly in an extremely insanitary condition, but these streets, though so numerous, are not in the beaten track of the pleasure tourist.

In the old intramural city, in which live about 40,000 people, the streets vary in width, but generally they are 6.8 meters (about 22 feet) wide, of which the sidewalks occupy about 7.5 feet.  In many streets the sidewalk at each side is not even 18 inches wide.  In the new, extramural town, the streets are generally 10 meters (32.8 feet) wide, with 3 meters (nearly 10 feet) for the sidewalks, and 7 meters (23 feet) for the wagonway.  There are few sidewalks in any except in the first four of the nine city districts.

More than two-thirds of the population live in densely inhabited portions of the city, where the houses are crowded in contact with each other.  The average house lot does not exceed 27 by 112 feet in size.  There are 17,259 houses, of which 15,494 are one-story, 1,552 are two stories, 186 are three stories, and only 27 are four stories, with none higher.  At least 12 in every 13 inhabitants live in one-story houses; and as the total civil, military, and transient population exceeds 200,000 there are more than 12 inhabitants to every house.  Tenement houses may have many small rooms, but each room is occupied by a family.  Generally the one-story houses have four or five rooms; but house rent, as also food and clothing, is rendered