Troppberg, Mountain summit in Gablitz and Tullnerbach, Lower Austria, Austria

Troppberg is a 542-metre summit in the northern Vienna Woods, on the boundary of Gablitz and Tullnerbach in Lower Austria. The peak lies about 120 metres from the Tullnerbach municipal border, within Gablitz. A stone lookout tower, the Troppbergwarte, stands on the highest point, and a roughly 50-metre radio mast with a viewing platform at 24 metres was built beside it in 1991.

In 1870 the Purkersdorf beautification society built the 11-metre stone Troppbergwarte on the summit, which still stands. A taller concrete lookout column with a platform at 20 metres followed in 1962 but was demolished in 1991. That same year the roughly 50-metre Troppberg radio tower was erected, with a viewing platform at 24 metres.

Since 2011 the Purkersdorf–Göttweig section of the Austrian Jakobsweg (Way of St. James) has run over the Troppberg, so pilgrims and day hikers share the marked paths. The peak is a classic Vienna Woods excursion destination, reached on waymarked trails from all directions, including a roughly 30-minute climb from the Wienerwaldhof in the west.

The mountain is best accessed in dry weather, as paths can become slippery after rain. Visitors should wear sturdy shoes and allow adequate time for the climb, especially if planning to visit the observation platform.

The 50-metre Troppberg radio tower, built in 1991, has a viewing platform at 24 metres; from there the panorama covers much of the northern Vienna Woods and parts of Vienna, and on good days reaches the Schneeberg and the Ötscher. It replaced a concrete observation column from 1962 that was demolished after less than 30 years.