Ocean water circulates around the world in streams called currents. The major currents have their own names.

Topographic maps show the elevations and slopes of hills, valleys, and other natural features by the use of contour lines.

Draw a series of contour lines on the map below using the elevations shown as a guide. The sea level elevation line is provided and you should draw contour lines at intervals of 20 meters.

Topographical maps are like regular maps in that they give the geographical positions, but they also give elevations of both manmade and natural features. Using the contour lines and contour intervals, provide a range for the elevations of the features on this map.

Rivers erode their channels and as they do so they go through different stages of development and create different features.

Rivers typically begin as a melting glacier or a collection of small streams high up in a set of hills. As the river waters flow downhill they reshape the land by eroding features and transporting materials such as stones, sand, and clay. Eventually the river ends in a lake or the ocean. The term river system is used to describe the river itself and all the water that flows into it.

Glaciers are large structures made of ice that gradually move down the sides of a mountain. As they do so, they carry tons of trapped rock and scrape and grind the mountain walls. The enormous and sustained force reshapes the mountain sides and slopes in its path and leaves behind deposits of rock carried from other areas.

The lines of latitude and longitude are used to locate points of the surface of the Earth. The lines of latitude run from East to West and the lines of Longitude run from North to South.

Maps are very valuable tools, but using them properly requires knowing several aspects of the way maps are made. Most maps have several features that are essential for using them to their full potential, but they are useful only if you know to use their many features.

Use the set benchmark points below to draw contour lines on the topographic map. The lines should be drawn in 20 foot intervals.

Use the benchmark points below to draw contour lines. The contour lines should be drawn at 20 foot intervals.

Use the benchmark points below to draw contour lines. The contour lines should be drawn at 20 foot intervals. When you complete the contour lines, fill each layer in with a different color. This worksheet has many different reference points to work off of.

Use the topographic to make a bar graph as you travel from Point A, B, C, D, E.

Take the points in order and make nice two dimensional chart to display this terrain.

You will use the map to answer a series of physical questions about the area. For example: Which letter is located at the highest land point?

Use the contour lines to label the elevations of each point on the map.

Where are those peaks and valleys?

Most of us have used digital or paper street maps to navigate when we don't know how to get somewhere, but not everyone has used a topographic map. So, what are these maps?

Topography maps show an area's natural and significant human-made features. These include major roads, urban areas, important buildings, and borders. They also indicate bodies of water, mountains, forests, and valleys.

In the sections below, I'll explain how to understand topography maps and what their colors, symbols, and lines mean.

How To Understand Topographic Maps

I mentioned that topography (or topographical) maps show an area's natural and important human-made features. These features are indicated by a few different markings:

Once you understand the significance of these markings, they will allow you to understand more about the world around you.

Lines

There are always plenty of lines of topographical maps, and each line type represents something different. Let's take a look at contour lines and other types of lines used to mark topographic features.

Contour Lines

Contour lines are typically wavy and circular and are one of the most important elements of topographical maps. They connect areas with equal elevations, showing where the elevation rises and how steeply.

How widely spaced out they are depends on how steep the land or mountain is. For instance, if the topography map shows a contour line for every 20 feet (6 meters) in elevation, steep mountains will have several tightly-packed contour lines, while flatter landscapes will have fewer.

For every five contour lines, there is an index contour where the elevation is labeled. You can easily spot the index contour because it is slightly thicker and darker.

Other Lines

Other lines on topography maps can vary in color and thickness and can be solid, dotted, or dashed.

Thin, black lines indicate paths and trails, while thick ones show a main road or highway. If you see a dashed line, it's a railway line, but a dotted line shows that an area is relatively flat.

Colors

Topography maps have various colors, including the following:

These colors have different shades to denote how built-up or densely populated an area is. For example, a dark red shaded area shows a busy, urban area, while a lighter red shade indicates a suburban area.

Symbols

You will see various symbols and shapes on any topographical map, and many of them are labeled.

For example, you might see a circular shape labeled as “dry lake” or a rectangular shape with a “gravel” label showing that it's a gravel pit.

Buildings are normally shown as small black dots, with large and important ones having their own symbols. Airports are depicted as diagonal crosses, while schools are tiny black squares with little flags on top.

Instead of placing a dot for every building, the map is shaded red or gray in densely-populated areas.

Understanding the Scale of Topography Maps

Since topographic maps usually represent large areas of land, they have a large scale. The U.S. Geological Survey (USGS) uses a scale of 1 to 24 inches (2.54 to 61 cm) , meaning every inch (2.54 cm) on the map shows 24 inches (61 cm) in real terms.

You can check your topography map's scale by looking in the bottom left or right-hand corner.

Topographical maps representing very large areas have larger scales, but maps showing more features in a smaller area have a smaller scale.

Conclusion

Topographical maps show an area's important natural and human-made features, including:

After familiarizing yourself with the lines, colors, and symbols mentioned in this article, you should be able to interpret topographic maps and spot interesting features.