HAMMINKELN, West Germany (AP) _ Want a 700-year-old romantic castle that comes with more than six acres of land? No money? It's all for free. Plus a cash gift of $600,000 and no ghosts to haunt you.

There are, however, some strings attached to the offer by the community of Hamminkeln, 60 miles north of Bonn, the West German capital.

''There are two conditions: that the new owner pledges not to use the castle for commercial purposes and to himself foot the bill for maintenance costs,'' Hamminkeln treasurer Heinz-Dieter Melzer said Thursday.

Maintenance costs for Ringenberg Castle, a few miles from the Rhine River, are estimated at $110,000 a year. Melzer said Hamminkeln, a town of 23,000, is unable to continue paying the upkeep.

So far, there are no takers.

The castle is presently used by several live-in artists.