The   Zytglogge   (pronounced   tsit-kloka)   is   a   landmark   medieval   tower   in   Bern, Switzerland. When   it   was   built   around   1218–20,   the   Zytglogge   was   a   squat   building   of   only   16 metres   in   height      and   served   as   the   gate   tower   of   Bern's   western   fortifications. When   the   rapid   growth   of   the   city   and   the   further   expansion   of   the   fortifications relegated   the   tower   to   second-line   status   at   around   1270–75,   it   was   heightened by   7   metres   to   overlook   the   surrounding   houses. After   the   city's   western   defences were   extended   again,   in   1344–46,   the   Zytglogge   was   converted   to   a   women's prison,   notably   housing   Pfaffendirnen   –   "priests'   whores",   women   convicted   of sexual   relations   with   clerics.   At   this   time,   the   Zytglogge   also   received   its   first slanted roof. In   the   great   fire   of   1405,   the   tower   burnt   out   completely.   It   suffered   severe structural    damage    that    required    thorough    repairs,    which    were    not    fully completed   until   the   last   restoration   in   1983. The   prison   cells   were   abandoned   and a    clock    was    first    installed    above    the    gate,    probably    including    a    simple astronomical   clock   and   musical   mechanism.   This   clock,   together   with   the   great bell   cast   in   1405,   gave   the   Zytglogge   its   name,   which   in   Bernese   German   means "time bell". In   the   late   15th   century,   the   Zytglogge   and   the   other   Bernese   gate   towers   were extended   and   decorated,   and   the   astronomical   clock   was   extended   to   its   current state.   In   1527–30,   the   clockwork   was   completely   rebuilt   by   Kaspar   Brunner,   and the    gateway    was    overarched    to    provide    a    secure    foundation    for    the    heavy machinery. The   Zytglogge's   exterior   was   repainted   in   1607–10,   including   the   introduction   of   the   large   clock   faces   which   now dominate the east and west façades of the tower. Following   at   least   two   more   re-stylings,   the   design   came   to   be   disliked   in   the   20th   century,   and   a   1929 competition   produced   the   façade   designs   visible   today:   on   the   west   façade,   Victor   Surbek's   fresco   "Beginning   of Time"   and   on   the   east   façade,   a   reconstruction   of   the   1770   design   by   Kurt   Indermühle.   In   1981–83,   the   Zytglogge was thoroughly renovated again and generally restored to its 1770 appearance. The   Bernese   German   Zytglogge   translates   to   Zeitglocke   in   Standard   German   and   to   time   bell   in   English.   A   "time bell"   was   one   of   the   earliest   public   timekeeping   devices,   consisting   of   a   clockwork   connected   to   a   hammer   that rang   a   small   bell   at   the   full   hour.   Such   a   device   was   installed   in   the   Wendelstein   in   Bern   –   the   tower   of   the Leutkirche   church   which   the   Münster   later   replaced   –   in   1383   at   the   latest;   it   alerted   the   bell-ringer   to   ring   the tower bells. The   name   of   Zytglogge   was   first   recorded   in   1413.   Previously,   the   tower   was   referred   to   as   the   kebie   ("cage", i.e., prison) and after its post-1405 reconstruction, the nüwer turm ("new tower").