4th June Christian (Catholic) Corpus Christi Body and Blood of Christ
The Feast of Corpus Christi, also known as the Solemnity of the Most Holy Body and Blood of Christ, is a significant event in the Roman Catholic liturgical calendar. This day is dedicated to celebrating and honouring the Eucharist—the Body and Blood of Jesus Christ, present in the consecrated host and wine. For those new to Catholicism, the Eucharist is central to Catholic faith, embodying the spiritual nourishment and presence of Christ among His followers.
https://www.reonline.org.uk/festival_event/the-most-holy-body-and-blood-of-christ-corpus-et-sanguis-christi/
4th June Muslin Eid Al Ghadir
Eid Al-Ghadeer is the commemoration of Prophet Muhammad’s (saw) final sermon at Ghadir Khumm, which took place on the 18th of Dhu al-Hijjah, 10 AH.Shias celebrate this incident as the basis for their acceptance of Imam Ali (a.s.) succession to the Prophet.
https://www.bbc.co.uk/bitesize/guides/zhnhsrd/revision/9
12th June Christian (Catholic) Feast of the Sacred Heart
The Feast of the Sacred Heart of Jesus holds a deeply significant place in the Catholic Church. It is a time dedicated entirely to honouring the boundless love, mercy, and compassion of Jesus Christ.
https://www.vaticannews.va/en/liturgical-holidays/solemnity-of-the-most-sacred-heart-of-jesus.html
16th June Sikh Martyrdom of Guru Arjan Dev Ji
On 16 June 1606, the Mughal Emperor Jahangir ordered that Guru Arjan Dev Ji, the fifth Sikh Guru be tortured and sentenced to death after the Guru had refused to stop preaching his message of God as started by Guru Nanak Dev Ji. The Guru was made to sit on a burning hot sheet while boiling hot sand was poured over his body. After enduring five days of unrelenting torture, Guru Arjan Dev Ji was taken for a bath in the river. As thousands watched he entered the river, never to be seen again. Accordingly, on the 16 of June of every year since 1606, the Sikhs commemorate the martyrdom of Guru Arjan Dev Ji, the fifth Guru and the first Sikh Martyr.
https://www.reonline.org.uk/festival_event/martyrdom-of-guru-arjan-1606/
17th June Muslim Al-Hijra
Al-Hijra is an annual Muslim festival marking the beginning of the Muslim year. It commemorates Mohammed’s move from Mecca to Medina and involves the exchange of gifts and the telling of stories about Muhammad.
https://www.reonline.org.uk/festival_event/islamic-new-year-al-hijra-ras-ul-am-muharram-1/
21stJune Pagan Midsummer Solstice /Litha / Alban Hefin
Summer Solstice marks the longest day of the year (hours of daylight) and is a time to celebrate the power of the sun and the abundance and growth of the natural world.
https://www.bbc.co.uk/religion/religions/paganism/holydays/summersolstice.shtml
26th June Muslim Ashura
Ashura, for Sunni Muslims, Ashura is seen as the day that the Prophet Nuh (Noah) disembarked from the Ark, as well as when the Prophet Musa (Moses) parted the Red Sea to allow safe passage for the Israelites out of Egypt. Followers observe it with fasting and special prayers in mosques, signifying its sacred nature.
In contrast, for Shia Muslims, Ashura is a solemn day: it is a day of mourning, commemorating the anniversary of the killing of Imam Hussein, the grandson of the Prophet Muhammad, during the Battle of Karbala in October 680 CE.
https://www.bbc.co.uk/news/world-middle-east-16047713
29th June Christian St. Peter and Paul
The feast of saints Peter and Paul is a solemnity, the highest rank for a liturgical feast and a holy day of obligation. Through their preaching, ministry and martyrdom, saints Peter and Paul helped to establish the Christian Church.
https://religionunplugged.com/news/2023/6/16/feast-of-saints-peter-and-paul-how-christians-around-the-world-celebrate