The Old City with its central Alter Platz (Old Square) and the Renaissance buildings with their charming arcaded courtyards is a major attraction. Notable landmarks also include:
Lindworm fountain of 1593, with a Hercules added in 1633
Landhaus - Palace of the Estates, now the seat of the State Assembly.
the Baroque cathedral, built by the then Protestant Estates of Carinthia
Hypo-Arena Football stadium
Minimundus, the "small world on lake Wrthersee"
the Kreuzbergl nature park with a viewing tower and observatory
the small but attractive botanical garden at the foot of Kreuzbergl, with a mining museum attached
Wrthersee, the warmest of the large Alpine lakes, with Europe's largest non-sea beach and lido taking 12,000 bathers on a nice summer day.
Maria Loretto peninsula with its newly renovated stately home, until recently in the possession of one of Carinthia's noble families, the Rosenbergs, but acquired lately by the city.
Tentschach and Hallegg castles.
A number of general high schools such as
Europa-Gymnasium, Austria's oldest
BRG Klagenfurt-Viktring with emphasis on arts (music and drawing)
ORG St. Ursula, a private Catholic institution
a Slovene-language Gymnasium
and senior high schools offering general-cum-professional education:
Two schools of Engineering: HTL Lastenstrasse and HTL Mssingerstrae
Two commercial high schools: Handelsakademie #1 and #2
a Slovene-language Commercial High School ("Handelsakademie")
a high school of catering, fashion and design
a school of pre-school education
a school of Alpine agriculture and nutrition science
a school of social management of the Caritas charity
Bernhard von Spanheim (1176 or 1181 1256), House of Sponheim, was Duke of Carinthia for 54 years from 1202
Johann von Viktring, (c.1270 1347) late medieval chronicler and political advisor to the Duchy of Carinthia
Jurij Japelj, (1744 1807) Slovene Jesuit priest, translator, and philologist
Lorenz Chrysanth von Vest (1776 in Klagenfurt 1840) Austrian physician and botanist.
Franciszek Ksawery Lampi, (1782 in Klagenfurt 1852), Polish Romantic painter
Friedrich Martin Josef Welwitsch (1806 in Maria Saal 1872) Austrian explorer, botanist, discovered Welwitschia mirabilis.
Matija Majar, (1809 1892), Carinthian Slovene Roman Catholic priest and political activist, went to school in Klagenfurt
Andrej Einspieler, (1813 1888) Slovene politician, Roman Catholic priest, journalist, "father of the Carinthian Slovenes"
Anton Janei, (1828 1869) Carinthian Slovene linguist, philologist, literary historian, went to school in Klagenfurt
Maximilian Daublebsky Freiherr von Sterneck zu Ehrenstein (1829 in Klagenfurt 1897) Admiral Austro-Hungarian Navy
Josef Stefan (1835 in Klagenfurt 1893) Carinthian Slovene physicist, mathematician, poet of the Austrian Empire
Hubert Leitgeb (1835 in Portendorf 1888) Austrian botanist
Gustav Adolf Franz Xavier Gugitz (1836 in Klagenfurt 1882) Austrian architect
Markus von Jabornegg zu Gamsenegg und Moderndorf (1837 in Klagenfurt 1910) Austrian government official, botanist
Emanuel Alexander Herrmann (1839 in Klagenfurt 1902) Austrian national economist, helped invent the postcard