Two additional calendars:
#1. Part of a round calendar, from around AD 300, was unearthed recently at Hadrian’s Wall in northern England. Holes arranged around a foot-wide copper-alloy ring allowed the Roman soldier who owned it to advance a peg to the next hole every two days. Much as on the Russian calendar-embroideries, a series of marks cling along the curve outside the pegholes, while the word September survives on the inner curve. The marks are ‘K’ for Kalends (first of the month, whence our word calendar), ‘N’ for Nones (fifth day); ‘ID’ for Ides (thirteenth) and ‘AE’ for Aequinoctium on Sept. 23, the fall equinox. (Source: Andrew Birley: “Artifact” Archeology Magazine 62.1  72.) The peg-moving design of this calendar suggests that the Minoans (Bronze Age inhabitants of Crete) also might have used the numerous shallow cups hollowed out around the perimeters of large flat rocks (e.g., at Vasiliki and Mallia) for calendrical purposes.
#2. In Bulgaria three or four centuries ago, someone incised a clever “perpetual” calendar onto a crutch-shaped staff, representing six months on each of two faces, up one side and down the other. (See image.) A cross at the bottom of one face marks the starting point as September 1, formerly the Church’s New Year, so this calendar-stick was probably devised by a priest. The last owner, however, a farmer, said he reckoned from the other side, which starts at the top with March 1—the agrarian New Year.
Each tally marks a day. The triangle below every seventh tally designates the week, while the elongation of every tenth tally groups the dates by tens. Example: Sept. 7 has a triangle, Sept. 10 an elongation; so it’s easy to count out that September has exactly 30 days: count 3×10, or count 4 sets of 7 triangles (28), plus 2 ticks (=30). Six months climb up that side of the crutch; the other six, starting with March, go down the other face. The stick’s owner explained that to determine which day of the week some date fell on, he needed to know the day March 2 fell on that year. Since March 2 has a triangle beneath it, every date with a lower triangle (week marker) automatically falls on the same day of the week that year (e.g., Tuesday for 2010, Friday for 1907 when the research was done), and the other six weekdays could be counted from the nearest triangle. Large Vs above the tallies mark important fixed holidays—e.g., Christmas on Dec. 25, Epiphany on Jan. 6.
(Source: D. Marinov, “Pateritsa,” Izvestię na Etnograficheskię Muzej vŭ Sofija 1  13.)
Actual translation of Marinov:
“Mr. [Dedo] Momchil Minev was born in the village Kara-Orman; his father was named Mino Gochov, and his mother Janka Lozeva; he passed away 23 November 1894.
According to the story of his son, Mino Momchilov, Mr. Momchil learned to use/read the tally-calendar from his mother Janka, who was a priest’s daughter and came from another village. This Mme. Janka learned to read this calendar from her father, who probably? learned from his father. And if we try to determine[?] by whom and when this method was first figured out, through tally-cuts to represent and find the holidays throughout the year, we will work it out thus [?]: to Mr. Momchil from his mother, from her father the priest; from him to his father—also a priest—which will lead to the fourth “belt” [generation?] back or a matter of 250 years. And if we take for certain that also Mme Janka’s grandfather didn’t devise the tally calendar but that he got it from his father—then we reach a very distant era, which serves as evidence that this tally-calendar dates from very long in the past… [?]
As is visible from the drawing given, this crutch is indistinguishable from other typical crutches. [?] Counting begins from September, from which, as is known, the Church New Year begins, and this shows that the author is indeed a priest. However, the months Sept., Oct., Nov., Dec., Jan., and February are counted and move from left to right; from March it turns around and the months are counted from right to left, March, April, May, June, July, and August. Straight cuts/lines represent ordinary days, and various angular and slanted cuts, placed above the straight cuts, represent various holidays. In order to know how many days have passed from Sept. 1st and how many remain till a certain holiday from a given day, there are longer straight lines/cuts beneath the short straight cuts; all such lines designate ten-day periods, that is, from one to the next there are ten days, the counting, however, must begin from September 1st. They know [give?] the month and the number of the day [date] on which a [certain] holiday falls. However, it is also necessary to know on what day of the week—Monday or Tuesday [etc.]—the sought-after holiday falls; so as to calculate that too, it is necessary to look at the little triangular grooves hollowed out below the short straight cuts; the stretch[?] from one groove to the next is a whole week. So as to know which day of the week this groove represents, you’ll need to know which day of the week March 2 fell on; if this day fell on Monday, then all the grooves throughout the year represent Monday; if the 2nd of March fell on Tuesday, these grooves will indicate Tuesday, and so on. (Ftnt: Mr. Argirov is wrong that these triangular grooves mark Sundays.)
Thus, this year, 1907, March 2 falls on Friday, so throughout the year till March 2, 1908, these grooves will indicate Friday.
[Can also see that:] Blagovets/Annunciation (March 25) will fall on Sunday; George’s Day (Apr. 23) on Mon.; St. Tsar Boris (May 2) on Wed.,; Sts. Cyril and Methodius (May 11) on Friday; Peter’s Day (June 29) on Friday; St. Ilija (July 20) on Friday; Preobrazhenie/Transfiguration of the Lord (Aug. 6) on Monday; Great Mother of God (Aug. 15) on Wed.; Kristov Day (Sept. 14) on Friday; Dimitrov Day (Oct. 26) on Friday; Rangelov Day (Nov. 8) on Thurs.; St. Nicholas (Dec. 6) on Thurs.; Koleda/Christmas (Dec. 25) on Tuesday; St. Basil (Jan. 1) on Tuesday; Epiphany (Jan. 6) on Sunday; Candlemas (Feb. 2) on Saturday.
[plus comments re Leap Year; comments re Easter]