# TT Circuit Assen

The TT Circuit Assen is a motorsport race track built in 1955 and located in Assen, Netherlands. Host of the Dutch TT, it is popularly referred to as "The Cathedral of Speed" by motorcycle racing fans. The venue has the distinction of holding the most Grand Prix motorcycle races every year (except 2020) since the series was created in 1949. It has a capacity of 110,000 spectators, including 60,000 seats. Since 1992, the circuit has also been part of the World SBK calendar except for the 2020 season.

## History

The original Assen track was first used for the 1926 Dutch TT (Tourist Trophy) race, after the first 1925 event was held on country roads through the villages of Rolde, Borger, Schoonloo and Grolloo, and organized by the Motorclub Assen en Omstreken. The brick- and semi-paved track had a length of 28.57 km (17.75 mi). The winner was Piet van Wijngaarden on a 500 cc Norton with an average speed of 91.4 km/h (56.8 mph). From 1926 on the Dutch TT was held at Assen on a street circuit through De Haar, Barteldsbocht, Oude Tol, Hooghalen, Laaghalen and Laaghalerveen.
In 1951 the Italian Umberto Masetti took the record on a 500 cc Gilera with an average speed of 162.35 km/h (100.88 mph). In 1954, Geoff Duke of Great Britain reached 170.69 km/h (106.06 mph). The circuit remained unchanged until 1955, when a whole new circuit was built by using a third of the original street circuit, joined with purpose-built sections, but less than a third of the length and much more like a modern road racing circuit.
In the period of 1999–2002, the circuit invested millions in upgrades. In 1999, the circuit management placed a new main grandstand and hospitality buildings. In 2000, a new Race Control tower was built, as well as 34 newly equipped pit boxes, a new media and medical centre. Between September 2001 and April 2002, another €9 million was spent on the enlargement of the paddock area from 40 to 60.000 square metres. This upgrade meant that the Veenslang and Ruskenhoek corners had to be altered. The main straight has also moved about 50 m (160 ft) eastwards and a new two-lane tunnel now connects the paddock with the main entrance road and the media accreditation / welcome centre. The Mandeveen and Duikersloot corners have been moved back by 10 metres to accommodate larger run-offs and gravel beds at the southern part of the circuit. That part of the track has also been resurfaced with new asphalt. In total, the circuit has been shortened from 6.049 to 6.027 km (3.759 to 3.745 mi). The total cost of these upgrades was €23 million.
In 2005, the grandstand at the Geert Timmer corner was slightly altered. In order to improve the gravel run-off length, the grandstand was made in a 'floating' manner to accommodate the extra space that was needed. The lay-out of the circuit was also slightly altered.
The circuit was fundamentally redesigned again in 2006, becoming the so-called A-Style Assen TT Circuit. All alterations aside, only one section of the circuit is original; the finish line never moved. On 21 September 2009 it was announced that a new chicane will be added, after a request from the A1GP organization, however A1GP was unable to start the 2009–2010 season and as a substitute the Superleague Formula replaced A1GP.

## Layout history

* Original Dutch TT Van Drenthe Circuit (1926–1954)
* Grand Prix Circuit (1984–2001)
* Grand Prix Circuit (2002–2004)
* Grand Prix Circuit (2005)
* Grand Prix Circuit (2006–present)
* Motorcycle Circuit (2010–present)

## Current racetrack

Assen race track was built in 1955, and initially had a length of 7.705 km (4.788 mi). The current track has a length of 4.555 km (2.830 mi) with the mixture of super fast flat-out and slow corners. The longest straight is 560 m (1,840 ft). The curves in Assen were traditionally banked and the surface is extremely grippy, so the riders were able to drive much faster on the course than other circuits. Today these sloped or curved bends have been modified due to safety issues.

### Innovation

On 6 July 2004, the organisation announced plans for an amusement park located to the north of the track. In 2006 the northern loop was removed and the length was shortened to 4.555 km (2.830 mi). The new centre is expected to be visited by 300,000 people, and the total investment is approximately €85 million.

## Events
### Current

* April: Superbike World Championship, Supersport World Championship, Supersport 300 World Championship, FIM Women's Circuit Racing World Championship, Northern Talent Cup
* May: Ducati Club Races
* June: Grand Prix motorcycle racing Dutch TT, MotoE World Championship Dutch eRace, ADAC Hansa Pokal Rennen
* July: Dutch Moto Classic
* August: Supercar Challenge Jack’s Casino Racing Days, Eurocup-3, BOSS GP, Porsche Carrera Cup Benelux, Sidecar World Championship, IDM Superbike Championship [de],
* September: Sidecar World Championship, British Superbike Championship, British Supersport Championship, Northern Talent Cup, ADAC Racing Weekend Assen, Tabac Classic Grand Prix
* October: Supercar Challenge Finaleraces

### Former

* Acceleration 2014 (2014)
* ADAC Formel Masters (2008–2011)
* ADAC GT Masters (2008–2011)
* ATS Formel 3 Cup (2004–2012)
* Champ Car World Series
** Bavaria Champ Car Grand Prix (2007)
* Deutsche Tourenwagen Masters (2019–2021)
* DTM Trophy (2021)
* European Truck Racing Championship (2004–2005, 2009)
* FIM Endurance World Championship (1979–1980, 1995–1996, 2003–2006)
* Formula 750 (1976–1979)
* Formula Renault 2.0 Germany (1997–1998, 2004–2005)
* Formula Renault 2.0 Netherlands (2003–2005)
* Formula Renault Northern European Cup (2006–2017)
* GT4 European Trophy (2011, 2013)
* Motocross World Championship (2015–2018)
* Porsche Carrera Cup Germany (1997)
* Prototype Cup Germany [de] (2023)
* Red Bull MotoGP Rookies Cup (2007–2019, 2023–2024)
* SMP F4 Championship (2017–2018)
* Superleague Formula
** Superleague Formula round Netherlands (2010–2011)
* Super Tourenwagen Cup (1996)
* TCR Europe Touring Car Series (2018)
* W Series (2019)

## Lap records

As of August 2024, the fastest official race lap records at the TT Circuit Assen are listed as:
| Category | Time | Driver | Vehicle | Event |
| Grand Prix Circuit: 4.555 km (2006–present) |||||
| BOSS GP/F1 | 1:17.109 | Ingo Gerstl | Toro Rosso STR1 | 2023 Assen BOSS GP round |
| BOSS GP/Formula Renault 3.5 | 1:20.478 | Antônio Pizzonia | Dallara T12 | 2023 Assen BOSS GP round |
| Champ Car | 1:20.727 | Dan Clarke | Panoz DP01 | 2007 Bavaria Champ Car Grand Prix |
| BOSS GP/GP2 | 1:23.160 | Juju Noda | Dallara GP2/11 | 2024 Assen BOSS GP round |
| Superleague Formula | 1:23.547 | Yelmer Buurman | Panoz DP09 | 2010 Assen Superleague Formula round |
| Class 1 Touring Cars | 1:26.123 | Fabio Scherer | Audi RS5 Turbo DTM 2020 | 2020 Assen DTM round |
| FA1 | 1:26.831 | Dani Clos | Lola B05/52 | 2014 Assen FA1 round |
| Formula Three | 1:31.903 | Markus Pommer | Dallara F306 | 2011 2nd Assen German F3 round |
| LMP3 | 1:32.023 | Jan Marschalkowski | Ligier JS P320 | 2023 Assen Prototype Cup Germany round |
| Superkart | 1:33.059 | Peter Elkmann | Anderson/VM | 2020 Dutch Superkart Grand Prix |
| CN | 1:33.364 | Alex Cascatău | Norma M20-FC | 2020 2nd Assen GT & Prototype Challenge round |
| GT3 | 1:33.743 | Mike Rockenfeller | Audi R8 LMS Evo | 2021 Assen DTM round |
| Formula Renault 2.0 | 1:34.963 | Gilles Magnus | Tatuus FR2.0/13 | 2017 Assen Formula Renault NEC round |
| Formula Regional | 1:35.384 | Emma Kimiläinen | Tatuus F3 T-318 | 2019 Assen W Series round |
| MotoGP | 1:36.558 | Valentino Rossi | Yamaha YZR-M1 | 2009 Dutch TT |
| Porsche Carrera Cup | 1:38.410 | Larry ten Voorde | Porsche 911 (992) GT3 Cup | 2023 Assen Porsche Carrera Cup Benelux round |
| Formula 4 | 1:38.474 | Michael Belov | Tatuus F4-T014 | 2018 Assen SMP F4 round |
| World SBK | 1:38.680 | Noriyuki Haga | Ducati 1098R | 2009 Assen World SBK round |
| Lamborghini Super Trofeo | 1:39.034 | Max Weering [nl] | Lamborghini Huracán LP 620-2 Super Trofeo EVO | 2020 2nd Assen Supercar Challenge round |
| 250cc | 1:40.340 | Álvaro Bautista | Aprilia RSA 250 | 2008 Dutch TT |
| ADAC Formel Masters | 1:40.409 | Dennis Vollmair | Dallara Formulino | 2009 Assen ADAC Formel Masters round |
| World SSP | 1:40.836 | Cal Crutchlow | Yamaha YZF-R6 | 2009 Assen World SSP round |
| TCR Touring Car | 1:43.563 | Dennis de Borst | Hyundai i30 N TCR | 2020 2nd Assen Supercar Challenge round |
| 125cc | 1:45.098 | Sergio Gadea | Aprilia RS125R | 2006 Dutch TT |
| GT4 | 1:45.223 | Reinhard Kofler [pl] | KTM X-Bow GT4 | 2021 Assen DTM Trophy round |
| Formula Renault 1.6 | 1:46.198 | Anton de Pasquale | Signatech FR 1.6 | 2014 Assen Formula Renault 1.6 NEC round |
| Pickup truck racing | 1:50.118 | Daniël de Jong | MWV6 Pick Up | 2014 Assen MW-V6 Pickup Series round |
| Truck racing | 2:10.057 | Antonio Albacete | MAN TGS | 2009 Assen ETRC round |
| Motorcycle Circuit: 4.542 km (2010–present) |||||
| MotoGP | 1:31.866 | Francesco Bagnaia | Ducati Desmosedici GP24 | 2024 Dutch TT |
| World SBK | 1:33.620 | Álvaro Bautista | Ducati Panigale V4 R | 2022 Assen World SBK round |
| Moto2 | 1:35.977 | Sergio García | Boscoscuro B-24 | 2024 Dutch TT |
| Formula Renault 2.0 | 1:37.177 | Steijn Schothorst | Tatuus FR2.0/13 | 2013 Assen Formula Renault 2.0 NEC round |
| World SSP | 1:37.607 | Nicolò Bulega | Ducati Panigale V2 | 2023 Assen World SSP round |
| MotoE | 1:39.632 | Alessandro Zaccone | Ducati MotoE | 2024 Dutch TT |
| Moto3 | 1:40.405 | Adrián Fernández | Honda NSF250RW | 2024 Dutch TT |
| Formula Renault 1.6 | 1:46.425 | Roy Geerts [pl] | Signatech FR 1.6 | 2013 Assen Formula Renault 1.6 NEC round |
| Supersport 300 | 1:48.952 | Jeffrey Buis | Kawasaki Ninja 400 | 2023 Assen Supersport 300 round |
| 250cc | 1:50.823 | Kilian Holzer | KTM RC4 R | 2023 Assen Northern Talent Cup round |
| Grand Prix Circuit: 5.997 km (2005) |||||
| MotoGP | 2:00.991 | Valentino Rossi | Yamaha YZR-M1 | 2005 Dutch TT |
| World SBK | 2:04.685 | Chris Vermeulen | Honda CBR1000RR | 2005 Assen World SBK round |
| 250cc | 2:05.191 | Sebastián Porto | Aprilia RSV 250 | 2005 Dutch TT |
| World SSP | 2:08.865 | Katsuaki Fujiwara | Honda CBR600RR | 2005 Assen World SSP round |
| 125cc | 2:13.536 | Héctor Faubel | Aprilia RS125R | 2005 Dutch TT |
| National Circuit: 3.851 km (2005) |||||
| Formula Three | 1:18.602 | Martin Hippe [fr] | Dallara F303 | 2005 Assen German F3 round |
| Formula Renault 2.0 | 1:20.762 | Renger van der Zande | Tatuus FR2000 | 2005 Assen Formula Renault 2.0 Netherlands round |
| Truck racing | 1:52.800 | Markus Oestreich | Volkswagen Titan | 2005 Assen ETRC round |
| Grand Prix Circuit: 6.027 km (2002–2004) |||||
| MotoGP | 1:59.472 | Valentino Rossi | Yamaha YZR-M1 | 2004 Dutch TT |
| World SBK | 2:02.395 | Colin Edwards | Honda VTR1000SP2 | 2002 Assen World SBK round |
| 250cc | 2:03.469 | Dani Pedrosa | Honda RS250R | 2004 Dutch TT |
| World SSP | 2:06.922 | Katsuaki Fujiwara | Suzuki GSX600R | 2003 Assen World SSP round |
| 125cc | 2:10.123 | Jorge Lorenzo | Derbi RSA 125 | 2004 Dutch TT |
| National Circuit: 3.904 km (2002–2004) |||||
| Formula Three | 1:15.928 | Thomas Holzer | Dallara F302 | 2004 Assen German F3 round |
| Formula Renault 2.0 | 1:18.067 | Pascal Kochem [nl] | Tatuus FR2000 | 2004 Assen Formula Renault 2000 Germany round |
| Grand Prix Circuit: 6.049 km (1984–2001) |||||
| 500cc | 2:02.471 | Tadayuki Okada | Honda NSR500 | 1999 Dutch TT |
| World SBK | 2:03.914 | Carl Fogarty | Ducati 996 RS | 1999 Assen World SBK round |
| 250cc | 2:05.696 | Valentino Rossi | Aprilia RSV 250 | 1999 Dutch TT |
| World SSP | 2:08.748 | James Whitham | Yamaha YZF-R6 | 2001 Assen World SSP round |
| 125cc | 2:13.225 | Noboru Ueda | Honda RS125R | 1999 Dutch TT |
| 80cc | 2:30.790 | Ian McConnachie [nl] | Krauser 80 | 1986 Dutch TT |
| National Circuit: 3.919 km (1981–2001) |||||
| World SBK | 1:23.110 | Raymond Roche | Ducati 888 SBK | 1992 Assen World SBK round |
| Super Touring | 1:27.325 | Laurent Aïello | Peugeot 406 | 1996 Assen STW round |
| Grand Prix Circuit: 7.685 km (1981–1983) |||||
| 500cc | 2:47.470 | Kenny Roberts | Yamaha YZR500 | 1983 Dutch TT |
| 250cc | 2:57.790 | Carlos Lavado | Yamaha TZ 250 | 1983 Dutch TT |
| 125cc | 3:05.620 | Ángel Nieto | Garelli 125 GP | 1983 Dutch TT |
| 50cc | 3:24.870 | Eugenio Lazzarini | Garelli 50 GP | 1983 Dutch TT |
| Grand Prix Circuit: 7.717 km (1976–1980) |||||
| 500cc | 2:54.500 | Virginio Ferrari | Suzuki RG 500 | 1979 Dutch TT |
| 350cc | 3:02.500 | Patrick Fernandez | Yamaha TZ 350 | 1977 Dutch TT |
| 250cc | 3:02.800 | Kork Ballington | Kawasaki KR250 | 1979 Dutch TT |
| 125cc | 3:13.200 | Ángel Nieto | Minarelli 125 GP | 1979 Dutch TT |
| 50cc | 3:33.500 | Eugenio Lazzarini | Kreidler 50 GP | 1977 Dutch TT |