Čerťák is a ski jumping stadium with two hills in Harrachov in the Czech Republic.

It was built in 1979 and both hill officially opened in 1980. The venue is most notable for being one of five ski flying hills in the world, though it also has three smaller hills close by. It is owned by the sports club TJ Jiskra Harrachov. Audience capacity is about 50,000. Despite being a flying hill, only two world records have ever set at Čerťák, both in the 1980s. It was also during this time, and into the early 1990s, that many horrific accidents occurred.

The hills are located on the north side of the mountain Čertova hora, not far from the border to Poland. The first hill in Harrachov was built in 1922, but at a different location in town. Later in the 1920s the first hill in Čerťák was built. It was eventually expanded and supplemented with more hills. The ski flying hill was built in 1979 and opened in March 1980.

The large hill in Harrachov was built at the same time as the ski flying hill, and renovated in 1992. This hill has a K-point of 125 m and a hill size of 142 m. The official record is 145.5 m, set by Janne Ahonen on 12 December 2004 during the 2004–05 World Cup season. The unofficial record is 151 m set by Martin Koch (Austria) on 17 December 2004 in a Continental Cup event.

The normal hill has K-point of 90 m, a hill size of 100 m and a hill record of 102.5 m. The two smaller hills have K-points of 70 m (hill record 77 m) and K-point 40 meters (hill record 43.5 m). The standard hill has plastic mats, allowing summer use.

The ski flying hill in Harrachov garnered an early reputation of being quite dangerous from which to jump. In its early years, jumpers achieved a significant height over the knoll, up to 12 m. The result of this height was that a gust of wind or error from the jumper could end catastrophically, and there were indeed many injuries from bad falls. During the World Championship in 1983, injuries were suffered by Steinar Bråten, Horst Bulau and Jens Weißflog. In 1985, Pavel Ploc suffered a violent crash. The venue was eventually closed by the FIS and rebuilt between 1989 and 1992, and has since kept the requirements from FIS. Accidents have still occurred, however: in 1992, Andreas Goldberger fell out of the air at the highest point of his jump and crashed very hard.

Date	Hillsize	Competition	Winner	Second	Third align=right|
12 December 1997	K90	WC	Masahiko Harada	Primož Peterka Dieter Thoma

Date	Hillsize	Competition	Winner	Second	Third
10 January 1981	K120	WC	Roger Ruud	Armin Kogler	Per Bergerud Hubert Neuper
8 January 1983	K120	WC	Holger Freitag	Markku Pusenius	Klaus Ostwald
9 January 1983	K120	WC	Pavel Ploc	Klaus Ostwald	Markku Pusenius
14 January 1984	K120	WC	Jiří Parma	Jens Weißflog	Pavel Ploc
11 January 1986	K120	WC	Matti Nykänen	Ernst Vettori	Jiří Parma
10 January 1988	K120	WC	cancelled
15 January 1989	K120	WC	Jan Boklöv	Risto Laakonen	Ladislav Dluhoš
12 January 1990	K120	WC	Dieter Thoma	Ladislav Dluhoš	Jiří Parma
16 January 1993	K120	WC	lack of snow
17 January 1993	K120	WC
14 December 1996	K120	WC	Kazuyoshi Funaki	Primož Peterka	Takanobu Okabe
15 December 1996	K120	WC	Primož Peterka	Andreas Goldberger	Kristian Brenden
19 December 1998	K120	WC	Janne Ahonen	Ronny Hornschuh	Kazuyoshi Funaki
20 December 1998	K120	WC	Janne Ahonen	Noriaki Kasai	Andreas Widhölzl
7 February 1999	K120	WC (rep FH)	Janne Ahonen	Lasse Ottesen	Jakub Sucháček
11 December 2004	HS142	WC	Adam Małysz	Janne Ahonen	Georg Späth
12 December 2004	HS142	WC	Janne Ahonen	Roar Ljøkelsøy	Jakub Janda
10 December 2005	HS142	WC	Andreas Küttel	Michael Uhrmann	Janne Ahonen
11 December 2005	HS142	WC	Jakub Janda	Janne Ahonen	Andreas Küttel
9 December 2006	HS142	WC	lack of snow
10 December 2006	HS142	WC
12 December 2009	HS142	WC
13 December 2009	HS142	WC
11 December 2010	HS142	WC	strong wind; rescheduled to Engelberg
12 December 2010	HS142	WC	strong wind; rescheduled to Zakopane
9 December 2011	HS142	WC	Gregor Schlierenzauer	Daiki Ito	Anders Bardal
10 December 2011	HS142	WC-T	Norway Tom Hilde Bjørn Einar Romøren Vegard Sklett Anders Bardal	Austria Thomas Morgenstern David Zauner Andreas Kofler Gregor Schlierenzauer	Slovenia Jernej Damjan Jure Šinkovec Peter Prevc Robert Kranjec
11 December 2011	HS142	WC	Richard Freitag	Thomas Morgenstern	Severin Freund

Date	Hillsize	Competition	Winner	Second	Third
28-29 March 1980	K165	KOP	Steve Collins	Armin Kogler	Tom Levorstad
19-20 March 1983	K185	SFWC	Klaus Ostwald	Pavel Ploc	Matti Nykänen
23 February 1985	K185	WC	Ole Gunnar Fidjestøl	Miran Tepeš	Jiří Parma
24 February 1985	K185	WC	strong wind
18 March 1989	K185	WC	Ole Gunnar Fidjestøl	Mike Holland	Jan Boklöv
19 March 1989	K185	WC	strong wind
21 March 1992	K185	SFWC(d1) / WC	Noriaki Kasai	Andreas Goldberger	Roberto Cecon
22 March 1992	K185	SFWC(d2) / WC	stopped and cancelled; strong wind
World Championships Overall (21-22 March)			Noriaki Kasai	Andreas Goldberger	Roberto Cecon
9 March 1996	K185	WC	Andreas Goldberger	Christof Duffner	Jaroslav Sakala
9 March 1996	K185	WC	cancelled
6 February 1999	K185	WC	next day on large hill
13 January 2001	K185	WC	Adam Małysz	Martin Schmitt	Risto Jussilainen
14 January 2001	K185	WC	Adam Małysz	Janne Ahonen	Martin Schmitt
10 March 2002	K185	SFWC	Sven Hannawald	Martin Schmitt	Matti Hautamäki
19 January 2008	HS205	WC	strong wind
20 January 2008	HS205	WC	Janne Ahonen	Tom Hilde	Anders Jacobsen
(night) 8 January 2011	HS205	WC	Martin Koch	Thomas Morgenstern	Adam Małysz
9 January 2011	HS205	WC	Thomas Morgenstern	Simon Ammann	Roman Koudelka
(night) 2 February 2013	HS205	WC	first event next day
3 February 2013	HS205	WC	Gregor Schlierenzauer	Robert Kranjec	Jan Matura
3 February 2013	HS205	WC	Gregor Schlierenzauer	Jan Matura	Jurij Tepeš
(night) 15 March 2014	HS205	SFWC-I	Severin Freund	Anders Bardal	Peter Prevc
17 March 2014	HS205	SFWC-T	strong wind

Date Length 5 January 1980   Ladislav Jirásko 59.0 m (194 ft)   6 January 1980   František Novotný 75.0 m (246 ft)   6 January 1980   Jaroslav Balcar 88.0 m (289 ft)   6 January 1980   Ivo Peterka 91.0 m (299 ft)   6 January 1980   Břetislav Počík 97.0 m (318 ft)   6 January 1980   Ladislav Jirásko 101.0 m (331 ft)   6 January 1980   Ivo Felix 103.0 m (338 ft)   6 January 1980   Ivo Felix 109.0 m (358 ft)   10 January 1981   Armin Kogler 122.0 m (400 ft)   6 February 1983   Pavel Ploc 122.0 m (400 ft)

Date Length 13 January 1985   Pavel Ploc 123.0 m (404 ft)   13 January 1996   Andreas Goldberger 129.0 m (423 ft)   14 January 1996   Jakub Sucháček 137.0 m (449 ft)   14 January 1996   Kazuyoshi Funaki 140.0 m (459 ft)   14 January 1996   Kazuyoshi Funaki 141.5 m (464 ft)   10 December 2004   Andreas Widhölzl 142.0 m (466 ft)   11 December 2004   Adam Małysz 143.0 m (469 ft)   12 December 2004   Janne Ahonen 145.5 m (477 ft)   17 December 2004   Martin Koch 151.0 m (495 ft)