Alexandra PalaceAl‧ex‧an‧dra Pal‧ace /ˌælɪɡzɑːndrə ˈpælɪs $ -zæn-/ (also Ally Pally informal) 
a large building in North London that was built in 1873 and is now used for conferences (=large business or political meetings) and concerts. It also has a famous metal tower from which the first television signals were broadcast by the BBC.
a large building in North London that was built in 1873 and is now used for conferences (=large business or political meetings) and concerts. It also has a famous metal tower from which the first television signals were broadcast by the BBC.