From Ada's letter to Van: He [Demon] and I have gamed at Nevada, my rhyme-name town, but you are also there, as well as the legendary river of Old Rus. (2.1)

Nevada blends Neva, the river flowing from Lake Ladoga through St. Petersburg (VN's home city and Russia's former capital) into the Gulf of Finland, with Ada. Nevada obviously has no Van in it. But Veen being the family name of Demon, Demon's cousin Dan and their children Van, Ada and Lucette, Ada does not make a mistake when she states that Van is also there. For, in Dutch veen means what neva means in Finnish: "peat bog."

In the Prologue to The Bronze Horseman (1833) Pushkin mentions the low and marshy banks of the Neva and the Finnish fisherman, a sad stepson of Nature:

Прошло сто лет, и юный град,
Полнощных стран краса и диво,
Из тьмы лесов, из топи блат
Вознёсся пышно, горделиво;

Где прежде финский рыболов,
Печальный пасынок природы,
Один у низких берегов
Бросал в неведомые воды
Свой ветхой невод,* ныне там
По оживлённым берегам
Громады стройные теснятся
Дворцов и башен; корабли
Толпой со всех концов земли
К богатым пристаням стремятся;
В гранит оделася Нева

(An age passed, and the young stronghold,
The charm and sight of northern nations,
From the woods’ dark and marshes’ cold,
Rose the proud one and precious.
Where once the Finnish fisherman,
Sad stepson of Nature, alone,
By low riverbanks’ a sand,
Cast into waters, never known,
His ancient net, now on the place,
Along the full of people banks,
Cluster the tall and graceful masses
Of castles and palaces; and sails
Hasten in throng to the rich quays
From all the lands our planet masters;
The Neva-river’s dressed with rocks)

On Antiterra (Earth's twin planet on which Ada is set) Pushkin's poem is known as Headless Horseman:

The year 1880 (Aqua** was still alive - somehow, somewhere!) was to prove to be the most retentive and talented one in his long, too long, never too long life. He was ten. His father had lingered in the West where the many-colored mountains acted upon Van as they had on all young Russians of genius. He could solve an Euler-type problem or learn by heart Pushkin's 'Headless Horseman' poem in less than twenty minutes. (1.28)

The Headless Horseman is a novel (1866), set in Texas, by Captain Mayne Reid. In Speak, Memory (Chapter Ten) VN tells about his childhood games with his cousin Yuri Rausch von Traubenberg and how they used to enact a scene from the Mayne Reid novel.

The name Nevada is derived from the Sierra Nevada mountains, which means "snow-capped mountain range" in Spanish. From The Desert Home by Captain Mayne Reid: We knew, from the appearance of the mountain, that it was one of those where the snow lies for ever, and which throughout Mexico are termed “Nevada,” or snowy.

*note the wonderful alliteration and a play on the river name; one is also reminded of Pushkin's lines in the Introduction to Ruslan and Lyudmila: Tam na nevedomykh dorozhkakh / sledy nevidannykh zverey (there, on trails unknown to man are the footprints of unseen animals)
**Demon's demented wife whose name and mania (poor Aqua believes that she learnt to understand the language of water) bring to mind nevedomye vody (unknown waters) mentioned by Pushkin in The Bronze Horseman

Happy New Year to everybody!

Alexey Sklyarenko (who never even tried to memorize The Bronze Horseman and whom it took more than twenty minutes to solve Ada)