[Purist]

Alright, having been basically delayed a week by the Net outage, I'll try this again.

Here's an update to the first listing, with new material for Brooklands, Lausitzring, Monza, and Montlhery. I've also decided to include the first few layouts of one more circuit that wasn't initially in there.

Brooklands
3.369 miles (5.422 km), 9 turns
Record: Raymond Mays, under 2:27.370 (over 82.300 mph); ERA B, 1937 (Voiturette)
2.267 miles (3.648 km), 9 turns
Record: Raymond Mays, 1:44.913 (77.790 mph); ERA B, 1937 (Voiturette)

Enna-Pergusa
3.030 miles (4.876 km), 14 turns
Record: Arturo Merzario, 1:21.760 (133.415 mph); Alfa Romeo T33/TT/12, 1975 (WSC Group 6)
3.010 miles (4.844 km), 10 turns
Record: Jo Bonnier, 1:26.400 (125.417 mph); Lola T210 Ford, 1970 (Group 6)
2.983 miles (4.800 km), 6 turns
Record: Mario Casoni, 1:17.400 (138.744 mph); Ford GT40, 1966 (WSC Group 7)

Lausitzring
2.840 miles (4.570 km), 14 turns
Record: Rene Rast, 1:35.241 (107.349 mph); Audi RS 5 Turbo, 2019 (DTM)
2.161 miles (3.478 km), 12 turns
Record: Lucas Auer, 1:16.193 (102.104 mph); Mercedes-AMG C 63, 2017 (DTM)
2.139 miles (3.442 km), 12 turns
Record: Jamie Green, 1:17.489 (99.374 mph); AMG-Mercedes C Class, 2005 (DTM)
2.817 miles (4.533 km), 14 turns
Record: Jan Lammers, 1:38.173 (103.299 mph); Dome S101 Judd, 2003 (FIA SCC LMP900)

Montlhery
2.116 miles (3.405 km), 15 turns
Record: Michel Ferte, 1:20.430 (94.711 mph); Venturi 600 LM, 1994 (FIA GT1)
4.847 miles (7.800 km), 21 turns
Record: Helmut Marko, 2:30.300 (116.096 mph); Porsche 917 Spyder, 1971 (Group 6)
3.927 miles (6.320 km), 15 turns
Record: Johnny Servoz-Gavin, 2:17.900 (102.518 mph); Matra M630 Ford, 1968 (Group 6)
2.071 miles (3.333 km), 8 turns
Record: Gijs van Lennep, 1:23.600 (89.182 mph); Porsche 906, 1966 (Group 6)
4.837 miles (7.784 km), 15 turns
Record: Jean Behra, 2:50.000 (102.431 mph); Maserati 300S, 1956 (Sportscar)
3.904 miles (6.283 km, 9 turns
Record: Jean Behra, 2:16.000 (103.341 mph); Gordini T24S 3.0, 1954 (Sportscar)
7.800 miles (12.552 km), 34 turns
Record: Achille Varzi, 5:20.100 (87.723 mph); Auto Union Type A, 1935 (GP 750 kg)
7.767 miles (12.500 km), 24 turns
Record: Louis Chiron, 5:06.000 (91.376 mph); Alfa Romeo Tipo B/P3 2.9, 1934 (GP 750 kg)

Monza Combined
6.276 miles (10.100 km), 19 turns
Record: Pedro Rodriguez, 2:48.100 (134.406 mph); Ferrari 312 P, 1969 (WSC Group 6)
6.214 miles (10.000 km), 11 turns
Record: Mike Parkes, 2:46.900 (134.035 mph); Ferrari 275 P2, 1965 (WSC Group 7)
4.281 miles (6.889 km), 14 turns
Record: Hermann Lang, 2:32.400 (101.126 mph); Mercedes-Benz W154, 1938 (GP 3.0L S/4.5L)
4.350 miles (7.000 km), 29 turns
Record: Bernd Rosemeyer, 2:56.400 (88.775 mph); Auto Union Type C, 1936 (GP 750 kg)
4.319 miles (6.950 km), 27 turns
Record: Tazio Nuvolari, 2:49.800 (91.569 mph); Alfa Romeo 8C-35, 1935 (GP 750 kg)
2.678 miles (4.310 km), 14 turns
Record: Hans Stuck, 2:13.600 (72.162 mph); Auto Union Type A, 1934 (GP 750 kg)
6.214 miles (10.000 km), 11 turns
Record: Luigi Fagioli, 3:13.200 (115.789 mph); Alfa Romeo Tipo B/P3 2.6, 1933 (F. Libre)
4.263 miles (6.860 km), 10 turns
Record: Luigi Arcangeli, 2:29.000 (103.000 mph); Maserati Tipo 26M 2.5, 1930 (F. Libre)

The full extent of the chicanery at Montlhery in the 1960s into the '70s is too much of a mess to readily suss out, with various pieces not matching up or making sense.

Although the combined course length is the same, the pre-War and post-War layouts at Monza are not the same. As an example, the current Parabolica is an opening corner, while the 1922-38 version was pretty much semi-circular.