May a woman visit a cemetery when she is a Nidah?
It is customary for women to avoid visiting a cemetery during the days that they are a Nidah. Some Poskim rule this applies even during the seven clean days, until she immerses in a Mikveh. Others rule it only applies during the actual flow and hence she may visit a gravesite during the seven clean days [as well as single girls may visit at all times that the cycle is not occurring]. Practically a woman may be lenient in a time of need to go during her clean days. Furthermore, if not going will cause her great distress then she may be lenient even when seeing the actual flow. Nevertheless in such a case it is best for her to stand four Amos away from the Kever. Based on above a woman may be lenient on the following instances at all times: 1) Yartzite of her parents. 2) She is leaving town and not returning for a while.
Does the above custom apply even to Kivrei Tzaddikim? Some write this custom applies even to Kivrei Tzaddikim. Others write it does not apply to Kivrei Tzaddikim. Many women are accustomed to only be stringent during the actual flow and not during the seven clean days [or by a single girl when she is not having her flow]. This is the widespread custom followed by women regarding going on Lag Baomer to Meiron, that they are only stringent when seeing the actual flow.
 See Taharah Kehalacha 14/129; Nitei Gavriel Aveilus 2/84
 Pischeiy Teshuvah Y.D. 195/19 in name of Chamudei Daniel; Chayeh Adam 3/38; Aruch Hashulchan 195/28; Kaf Hachaim 88/12; Kitzur Dinei Taharah 3/25
 Chayeh Adam 3/38; M”B 88/7; Kaf Hachaim 88/12; Shiureiy Shevet Halevy p. 274; See Nitei Gavriel ibid that also brings from: Tirosh Veyitzhar 146; Taharas Yisrael 195/51; Kneses Yechezkal Sefaradi “Nun” 89; Maharam Shick in Hakdama.
 Shulchan Melachim Dinei Nidda Veyoledes 5 [p. 35]; Peri Hasadeh 4/93 [questions Chayeh Adam]; Taharah Kehalacha ibid footnote 279; See Nitei Gavriel ibid that also brings from: Chemdas Moshe 62; Leket Hakemach 88; Beir Mordechai 195; Divrei Shalom 4/154
 “As otherwise any single girl or woman, whether she is still a Besula or is widowed or divorced will never be able to go to a cemetery” [Shulchan Melachim ibid]
 Shiureiy Shevet Halevi p. 274; Taharah Kehalacha ibid
 Daas Torah 88 in name of Chemdas Moshe 62; Shulchan Melachim Dinei Nidda Veyoledes 5 [p. 35]; Nitei Gavriel ibid; Taharah Kehalacha ibid
 Shiureiy Shevet Halevi ibid; Nitei Gavriel ibid; Taharah Kehalacha ibid
 Shulchan Melachim ibid; Nitei Gavriel ibid; Taharah Kehalacha
 Shulchan Melachim ibid
 Taharah Kehalacha 14/130
 Chibas Yerushalayim “Ranenu Tzaddikim” 3, brought in Taharah Kehalacha ibid footnote 283; See Nitei Gavriel ibid that also brings from: Kneses Yechezkal Sefaradi “Nun” 89 that in Bagdad the custom was to avoid visiting Kivrei Tzaddikim until they went to Mikveh.
 Beir Mordechai in name of Asher Ledavid p. 35, brought in Taharah Kehalacha ibid footnote 283
 Taharah Kehalacha ibid; I was told by Rav Moshe Y. L. Landau, chief Rabbi of Bnei Brak, that practically this is the custom a woman is to follow and hence they are not to go to the Ohel when seeing an actual flow but they may go during the other days.
 Taharah Kehalacha ibid in name of “Elderly women of prestige families” in Yerushalayim.