Despite leveling after 1900, especially in matters of vocabulary and phonetics, a number of dialects still exist in Russia. Some linguists divide the dialects of Russian into two primary regional groupings, “Northern” and “Southern”, with Moscow lying on the zone of transition between the two. Others divide the language into three groupings, Northern, Central (or Middle) and Southern, with Moscow lying in the Central region. All dialects also divided in two main chronological categories: the dialects of primary formation (the territory of the Eastern Rus’ or Muscovy, roughly consists of the modern Central and Northwestern Federal districts); and secondary formation (other territory). Dialectology within Russia recognizes dozens of smaller-scale variants. The dialects often show distinct and non-standard features of pronunciation and intonation, vocabulary and grammar. Some of these are relics of ancient usage now completely discarded by the standard language.
The Northern Russian dialects and those spoken along the Volga River typically pronounce unstressed /o/ clearly (the phenomenon called okanye/оканье). Besides the absence of vowel reduction some dialects have high or diphthongal /e~i̯ɛ/ in the place of Proto-Slavic *ě and /o~u̯ɔ/ in stressed closed syllables (like in Ukrainian) instead of Standard Russian /e/ and /o/. In morphology it has an interesting feature as a post-posed definite article -to, -ta, -te similarly existing in Bulgarian and Macedonian.
In the Southern Russian dialects unstressed /e/ and /a/ following palatalized consonants and preceding a stressed syllable are not reduced to [ɪ] (like in the Moscow dialect), being instead pronounced /a/ in such positions (e.g. несли is pronounced [nʲasˈlʲi], not [nʲɪsˈlʲi]) – this is called yakanye/яканье. Consonants include a fricative /ɣ/, a semivowel /w~u̯/ and /x~xv~xw/, whereas the Standard and Northern dialects have the consonants /ɡ/, /v/, final /l/ and /f/, respectively. In morphology it has a palatalized final /tʲ/ in 3rd person forms of verbs (this is unpalatalized in the Standard and Northern dialects). Some of these features such as akanye/yakanye, a debuccalized or lenited /ɡ/, a semivowel /w~u̯/ and palatalized final /tʲ/ in 3rd person forms of verbs are also present in modern Belarusian and some dialects of Ukrainian (Eastern Polesian), indicating a linguistic continuum.
The city of Veliky Novgorod has historically displayed a feature called chokanye/tsokanye (чоканье/цоканье), where /tɕ/ and /ts/ were confused. So, цапля (“heron”) has been recorded as ‘чапля’. Also, the second palatalization of velars did not occur there, so the so-called ě² (from the Proto-Slavic diphthong *ai) did not cause /k, ɡ, x/ to shift to /ts, dz, s/; therefore where Standard Russian has цепь (“chain”), the form кепь [kʲepʲ] is attested in earlier texts.
Among the first to study Russian dialects was Lomonosov in the 18th century. In the 19th, Vladimir Dal compiled the first dictionary that included dialectal vocabulary. Detailed mapping of Russian dialects began at the turn of the 20th century. In modern times, the monumental Dialectological Atlas of the Russian Language (Диалектологический атлас русского языка [dʲɪɐˌlʲɛktəlɐˈɡʲitɕɪskʲɪj ˈatləs ˈruskəvə jɪzɨˈka]), was published in three folio volumes 1986–1989, after four decades of preparatory work.