A covered wagon is a horse-drawn vehicle that was used by pioneers in the 19th century to travel across the Great Plains of the United States. The speed of a covered wagon was determined by the number of horses pulling it and the terrain it was traveling on. On average, a covered wagon could travel about 2-3 miles per hour on flat terrain. However, if the terrain was hilly, the wagon's speed could be reduced to about 1 mile per hour.