Allow me to talk briefly about Sunday's Vasaloppet for those who are not familiar with the sports' history.
Back in the days there were three, four big races.
Norway:Holmenkollen (XC since 1900)
Finland: Lahti (since 1923) also known as Lahti Ski Games)
Sweden: Vasaloppet (since 1922, televised since 1966) and/or Svenska Skidspelen, english: Swedish Ski Games (from 1947 but not always in Falun).
If you don't count Worlds or Olympics then these are then only races with history, prestige, media coverage and and reoccurring venue (-1p for Svenska Skidspelen) enough to be called classics.
Major changes to the races:
Holmenkollen: Shorter and shorter rounds, from interval to masstart, alternating between skate and classic.
Lahti: If don't misremember it has been both 30 and 50km historically, nowadays it is skiathlon.
Svenska Skidspelen: changing venues, from the start 30km, now it is a mini-tour.
Vasaloppet: Pretty much the same tracks as in year 1922, classic mandatory.
If I would "translate" it to cycling races, for fun, at least how they used to be:
Holmenkollen: LBL (the oldest, also much climbing)
Lahti: RvV (the course used to have very steep but short climbs)
Vasaloppet: MSR (length, some strategical climbs)
Sv. Skidspelen: Fléche Wallonne maybe? I don't know
(A precursor to the Swedish Ski Games can be said to be the Nordic Ski Games, first held 1901 in Stockholm, so between 1901-1922 Holmenkollen and the Nordic Ski Games were the only two really "international" competitions.)
There were some other fun historical races, maybe I will write some about them. And the history of skiing in Russia I know almost nothing about.