TAR records for the countries visited (not counting USA and TAR8) as of S23:
China and India are the most visited countried by season (10 each).
Both countries also hold the record for the most number of official pit stops (15 each).
Only three countries have been visited three seasons on a row: India (S12,S13,S14), China (S16,S17,S18), and Indonesia (S21,S22,S23)
Portugal has the largest span between visits (18 seasons: S3 & S23)
Oceania has the largest span of not being visited by TAR (4 seasons: S14,15,16,17)
Only S2 didn't visit Europe.
Only S1 has Africa as its first continent visited.
When South America is the first continent visited in a season, the route would always go eastward except for S13.
S7 has the least number of Asia legs (1 double-length leg in India)
S1, S6, and S10 has the longest back-and-forth pattern of continents:
S1: Africa/Europe/Africa/Europe
S6: Europe/Africa/Aurope/Africa
S10: Africa/Europe/Africa/Europe
Most visited city (not counting flight connection cities(ahem.Frankfurt.ahem)): Amsterdam (5) (Every season that visited The Netherlands had to go through Amsterdam, including S19's stopover)
Seasons that have the most number of new countries visited:
S3 (11); S1 (10); S5 (9); S6 (7); S10 (6)
...and the least:
S21, S22, S23 with (0).