Railroad Antimonopoly Act of 1985 - Amends the Sherman Act to prohibit any owner rail carrier from monopolizing a route by denying any shipper or other rail carrier the use, on reasonable terms, of a facility which is the sole facility over which bulk commodities must be moved to connect with the track of a competing rail carrier or to reach the destination of shipment. Bars any rate restriction under this Act if the owner rail carrier permits a competing carrier to use such sole facility. Specifies procedures for determining rates for the use of a sole facility if there is no competition. Prohibits an owner rail carrier from conditioning the use of a sole facility upon use of other facilities.

Permits a shipper to elect to connect with a water carrier instead of, or in addition to, a competing rail carrier at the first connection point, provided that the cost of connecting with the water carrier is no greater than the cost of connecting with the competing rail carrier, or the owner rail carrier is reimbursed for the difference in cost.

Entitles any person injured by a violation of this Act to bring an action to recover damages and to seek injunctive relief as provided under the Clayton Act.