This photograph shows a partially enclosed covered arena. Indoor arenas are invaluable for wintertime riding. In many parts of the US, covered arenas are sufficient for most weather and often times stay cooler in the hot summer months. In colder winter climates, however, walls to block cold blasts of wind are necessary. This arena pictured is enclosed on three sides with an open side on the south. Leaving one wall open on a covered or indoor arena can help keep dust down, fresh air circulating, and stimulate a small breeze in summer months.