Visited this village in Arcadia situated between Vytina (Βυτίνα) and Lagadia (Λανγάδια) for a trail race held in September 2015.
It takes about 2 hours and half drive from Athens. After passing Vytina, you turn right at a sign saying “Valtesiniko” and continue about 15 min.
We thought it was called Βαλτεσίνικο, but it was actually Βαλτεσινίκο the accent falling on the latter i.
There are some attractive stone made buildings, but maybe not as attractive as some Arcadian villages like Stemnitsa.
I do not know the official number of inhabitants. The landlady of our B&B said it should be about 300. We saw a post office and KEP (public service office), but not bank.
There is some tourist activities, especially in the winter season, as Mainalo Ski Centre is not far. There are 4 or 5 hotels/B&B in and around the village.
Another activity you can enjoy here is trekking. Valtesiniko is one of the bases of Menalon Trail ( http://menalontrail.eu/ ).
There are two tavernas in the central (lower) square of the village. One is called Vasilikos and the other one called Klimataria.
Valtesiniko itself does not have any monument of note. Agios Nikolaos in the vicinity is well worth a visit (abandoned, but was open for visitors).