Holy Days - or Solemnities - are special days when we reflect on a particular mystery of our faith or remember a particular saint. They’re so important that the Church asks us to attend Mass on these days, even if they are not on a Sunday.
 

Holy Days of Obligation are the days, other than Sundays, on which we attend Mass and refrain from unnecessary work. On these feast days, we celebrate the blessings that God has given us through Jesus and the Saints.

There are 6 Holy Days of Obligation* that are celebrated in the United States.

• January 1—New Years Day - Mary, Mother of God
• 40th day after Easter—Ascension
• August 15—Assumption of the Blessed Virgin Mary
• November 1—All Saints Day
• December 8—Immaculate Conception
• December 25—Christmas - the Nativity of Our Lord Jesus Christ

*Please note that when a Holy Day falls on a Saturday or on a Monday, Mass is optional. (Canon 1246 §2 of the Code of Canon Law)

Holy Day Masses are celebrated as follows:
Holy Day (Evening) Vigil-
    6 pm at Blessed Sacrament Church
Holy Day (Daytime) Mass- 
    8:30 am at Blessed Sacrament Church
    12:05 pm at Holy Trinity Church
    6 pm at Holy Trinity Church