The Conestoga wagon is a heavy, broad-wheeled covered wagon

Covered wagon

The covered wagon, also known as a Prairie schooner, is an icon of the American Old West.Although covered wagons were commonly used for shorter moves within the United States, in the mid-nineteenth century thousands of Americans took them across the Great Plains to Oregon and California...

 that was used extensively during the late 18th century and the 19th century in the United States

United States

The United States of America is a federal constitutional republic comprising fifty states and a federal district...

 and sometimes in Canada

Canada

Canada is a North American country consisting of ten provinces and three territories. Located in the northern part of the continent, it extends from the Atlantic Ocean in the east to the Pacific Ocean in the west, and northward into the Arctic Ocean...

 as well. It was large enough to transport loads up to 8 ton

Ton

The ton is a unit of measure. It has a long history and has acquired a number of meanings and uses over the years. It is used principally as a unit of weight, and as a unit of volume. It can also be used as a measure of energy, for truck classification, or as a colloquial term.It is derived from...

s (7 metric tons), and was drawn by horses, mules or oxen. It was designed to resemble a boat, to help it cross rivers and streams, though it sometimes leaked unless one caulked the wagon.
The first known mention of a "Conestogoe waggon" was December 31, 1717 in the accounting log of James Logan after purchasing it from James Hendricks.