When the Belvedere Hotel opened its doors on December 14, 1903, it became Baltimore’s first luxury hotel. Off the posh lobby of the Beaux Arts–style building was the Owl Bar, then known simply as the Bar Room. Because it served alcohol, admission was restricted to men. The bar quickly became one of the city’s most popular and notorious watering holes, frequented by clientele ranging from businessmen and politicians to bookies and gangsters. Although the spittoons are gone, today the Owl Bar looks much as it did when it opened. The…