The broad tree-lined boulevard that streaks eastwards from Gornji Grad towards Tvrđa is famed throughout Europe for harboring one of the best-preserved ensembles of Art Nouveau houses in this corner of the continent. Ranked side by side on the north side of the avenue (numbers 12 to 22), they were commissioned by filthy-rich industrialists and hot-shot lawyers in the years just before World War II. Wilim Karl Hofbauer, Ante Slaviček and Franz Wybird were the Osijek-based architects responsible for most of the work. Take a look at the twirly-haired goddesses peering down from no.22, or the gargoyle-like faces perusing passers-by from the façade of no. 12, to get an idea of the fanciful decorative tastes of the era. On the opposite side of the road, the main post office (built in 1912) on the corner of Europska Avenija and Kardinala Stepinca is an impressive example of the more functional, less frivolous architecture of the epoch.