hideaways
... that some members of the United States Congress are assigned secret offices called hideaways whose locations may be unknown even to their own staff?
... that some members of the <a href="./United_States_Congress" id="mwBX8" rel="mw:WikiLink" title="United States Congress">United States Congress</a> are assigned secret offices called <b id="mwBYA"><a href="./Hideaway_(U.S._Senate)" id="mwBYE" rel="mw:WikiLink" title="Hideaway (U.S. Senate)">hideaways</a></b> whose locations may be unknown even to their own staff?