oder (ohne Lücke) zusammengefügt, nicht durchbrochen would be other German words conveying the meaning of "geschlossen"; the area is cohesive, exactly delineated, defined, demarcated and not interrupted or broken up by areas used for other purposes; enclosed/enclosure/inclosed or confined within one limited area IMO also relate to the German "geschlossen". In Das Deutsche Wörterbuch (Jacob und Wilhelm Grimm): geschlossen, see meaning 1:
http://germazope.uni-trier.de/Projects/WBB/woerterbuecher/dw...
"bei den korbmachern dicht gefügtes, nicht durchbrochenes flechtwerk"
regarding break(s):
in the sense of "without an opening/a breach for other things/purposes".