So, based on a discussion on the RTD discord, I've put together a little list.

It consists of the 50 racetracks (paved, closed circuits used for car or motorcycle racing) that, in my opinion, have had the most influence on, or best show the design patterns and trends of, race track design - good, bad, and otherwise. These tracks come from the entire history of racing, around the world, although they are not merely the most important and prestigious ones - many are, although there might be a few surprises. Tracks with interesting changes throughout their history are prioritized - they show more about design with each track. I am very willing to hear criticism and suggestions! I'm sure I missed something... But remember, this is in terms of influential design, not the best or most interesting tracks.

The list, divided into 5 eras:

-----------------------------Pre-war---------------------------

Milwaukee - 1903 - USA - longest-lived automobile racetrack, showed Americans that horse tracks would be a good place to start

Targa Florio - 1906-1977 - ITA - most prestigious of many long road circuits, often imitated, never duplicated

Isle of Man - 1907 - UK - the other great road circuit, has managed to hang on to the present throuhg various minor changes

Brooklands - 1907-1939 - UK - world's first permanent circuit, introduced the idea of banking

Indianapolis - 1909 - USA - showed us how to name oval turns and so much more, through many surfaces, yet always a test

Santa Monica - 1909-1918 - USA - the pre-eminent American road circuit, but started the trend of more reasonable distances

Los Angeles Motordrome - 1910-1913 - USA - first of the board tracks, started the obsession with "higher and faster"

----------------------------Inter-war-------------------------

AVUS - 1921-1998 - GER - one of the first test tracks, and steepest of all banking. Shrunk over time as tastes changed

Monza - 1922 - ITA - world's first permanent road course, still recognizable and loved through many changes

Le Mans - 1923 - FRA - another road track offering a different type of test. Multiple changes and some permanent sections, especially the controversial chicanes

Linas-Montlhery - 1924-2001 - FRA - interesting take on a roval and probably the first purpose-built track to include many medium and slow turns

Spa - 1925 - BEL - one of the most beloved road tracks, transformed later to a still long and challenging permanent one

Reims-Gueux - 1926-1972 - FRA - exemplified early road tracks with long, dangerous straights

Nurburgring - 1927 - GER - the biggest and most challenging permanent circuit of them all, later merged with a more modern design

Monaco - 1929 - MON - the first tight city circuit, now the most prestigious of all, despite increasing incompatibility with modern cars

Donington - 1931 - UK - early example of a smaller track, with small changes over time but still maintaining character

Hockenheim - 1932 - GER - one of the first times that grandstands were a serious consideration for a road track. Transformed by the most controversial redesign of all time

Roosevelt - 1936-1939 - USA - decades ahead of its time, a compact, flat, slow track that failed almost immediately but would be recognizable today

Interlagos - 1940 - BRA - inspired by the preceding, created the Brazilian style of sweeping corners

--------------------------Classic era------------------------

Silverstone - 1948 - UK - one of many post-WW2 airfield tracks, has changed many times as tastes dictate

Zandvoort - 1948 - NED - big sweeping track later turned tight and technical, soon to answer the question of whether this still works for modern F1

Darlington - 1950 - USA - created the template stock car racing still uses 70 years later, and shows ovals don't have to be boring

Sebring - 1950 - USA - another airport track that changed in different ways without quite losing its character

Buenos Aires - 1952 - ARG - father of many Argentinian tracks and one of the first to include many layouts, tight and twisty as well as open and fast

Imola - 1953 - ITA - reasonably sized but still very fast when built, now a very different track for reasons most know

Willow Springs - 1953 - USA - the first permanent road course in the US, wide open spaces set the standard for many club tracks, layout unchanged today

Road America - 1955 - USA - a very different kind of test, winding through forests with different types of turns, considered a major test for decades

Assen - 1955 - NED - a twisty and beloved semi-permanent track, with multiple rounds of controversial changes

Daytona - 1959 - USA - turned stock car racing back into a contest of speed, got everyone watching the race finish, and added the world's best roval to boot

Charlotte - 1960 - USA - created a balance of speed and handling that inspired a huge round of imitators decades later

Bristol - 1960 - USA - the flip side of American oval racing, short yet fast and aggressive, with recent struggles illustrating how details matter in short tracks

Suzuka - 1962 - JPN - arguably the first "all-around" permanent circuit, one of the most liked, and with one of the best-documented design processes

Fuji - 1963 - JPN - a failed attempt to bring the big banked oval internationally, but made something great out of it, and became a very different track over time

Tsukuba - 1966 - JPN - short and simple, but emblematic of worldwide club and time trial tracks

Red Bull Ring - 1969 - AUT - first an incredibly fast track for its size, then sliced in half to make a very different challenge

------------------------Modern era----------------------------

Nivelles-Baulers - 1971-1981 - BEL - one of the first attempts to make a truly safe track, with turns that would look familiar today, but widely considered a boring failure

Luanda - 1972 - ANG - another attempt at an advanced and safe track (world's first gravel traps), with an oval, in Africa to boot, but doomed by politics and a boring layout

Misano - 1972 - ITA - another safe, tight track, but faster and better-liked. One of the few tracks to be reversed

Long Beach - 1975 - USA - father of American street races, showing 90 degree turns can be interesting, especially with others in the mix

Jerez - 1986 - ESP - emblematic of a series of bland, flavorless tracks of this age, full of medium-speed turns and compromises

Hungaroring - 1986 - HUN - corner after corner, interesting to drive but rarely to race, used more as a cautionary tale than anything else

Barcelona - 1991 - ESP - perhaps the most average F1 track, mixing corners but rarely inspiring, and often criticized for boring races over time

-------------------Post-modern era---------------------------

Houston - 1998-2001 - USA - the progenitor of an unfortunate trend of low-effort street courses plopped in any city willing to pay for them

Sepang - 1999 - MAY - Tilke's first complete design, probably one of the most influential ever, pioneering the modern "overtaking zone" with technical sections in between

Dubai Autodrome - 2004 - UAE - first of many "showoff tracks" by governments with too much money, acres of paved runoff between sand, a true multi-purpose design

Istanbul - 2005 - TUR - Tilke's best-liked design, with more challenge and signature elements - many attempts to copy its long multi-apex corner

Monticello - 2008 - USA - biggest of a series of "resort tracks", catering more towards lapping (often supercars) - winding, hilly, intended to challenge amateurs

Yas Marina - 2009 - UAE - One of a few recent efforts that seem to care more about their flashy surroundings than the racing itself, with flavorless results

Austin - 2012 - USA - an attempt to take inspiration from many popular tracks with a little extra flair, leading to one of the most controversial designs of all time

Hanoi - (2020) - VIE - emblematic of a new era of street circuits, mixing long technical sections with longer straights. An attempt to accomodate them for extreme modern F1 cars - results TBD