Markers were uscd to designate the known positions of enemy units. Although they never caught on, the result was usually a very tense and exciting game. The drawback was that an opponent that you could trust was absolulely vital. Across the Potomac is just such a game, but can be played on a single map, solo if necessary. A game turn starts with an administrative phase.
Players receive reinforcements, make any required withdrawals and roll a die to determine weather.
Bad weather has a very detrimental effect on movement. Both players complete this phase simultaneously. The Confederate player turn starts with the allocation of command points. A player can spend his command points on one of three functions. Units involved are removed from the map and placed on a seperate battle card in two opposing groups.