Since these two localities are linked only by a single bridge over the Spree river , the OberbaumbrÃ 1\/4 cke , this joining seemed awkward to many residents . The two areas could not agree on where the new borough 's town hall should be . Since the two areas are linked only by one single bridge over the Spree River , the OberbaumbrÃ 1\/4 cke , The two areas not being able to agree on a common location for the future borough 's city hall , the present location in Friedrichshain was decided by tossing a five-Mark coin .