Mad Vallis is a vallis (valley) in the

Hellas quadrangle The Hellas quadrangle is one of a series of 30 quadrangle maps of Mars used by the United States Geological Survey (USGS) Astrogeology Research Program. The Hellas quadrangle is also referred to as MC-28 (Mars Chart-28). The Hellas quadrangle c ...

of Mars, with its location centered at 56.5° S and 283.9° W. It is 524 km long and was named after the Mad River in

Vermont Vermont () is a state in the northeast New England region of the United States. Vermont is bordered by the states of Massachusetts to the south, New Hampshire to the east, and New York to the west, and the Canadian province of Quebec to ...

, USA.

References

Valleys and canyons on Mars Hellas quadrangle {{Mars-stub