In Barton Enterprises Inc., v. County of Ramsey, 390 N.W.2d 776 (Minn. 1986), the taxpayer operated a business, selling asphalt and oils for use in road construction and other commercial uses. The asphalt and oils were stored in 11 large oil tanks, ranging in capacity from 100,000 to more than 4 million gallons in capacity. The tanks, interconnected by pipes, use pumps to transfer the oils from receiving to loading stations, to blend the oils to the desired grades, and to maintain the specified grade of the asphalts. The Minnesota Supreme Court held that shelter function need not be the sole or even primary purpose of the structure in order to be taxable real property.