High Quality Content by WIKIPEDIA articles! In The Church of Jesus Christ of Latter-day Saints (LDS Church), a temple is a building dedicated to be a House of the Lord, and they are considered by Church members to be the most sacred structures on earth. Upon completion, temples are usually open to the public for a short period of time (an "Open House"). During the Open House, the church conducts tours of the temple with missionaries and members from the local area serving as tour guides, and all rooms of the temple are open to the public. The temple is then dedicated as a "House of the Lord", after which only members who are deemed worthy are permitted entrance. Thus, they are not churches (meetinghouses) but rather places of worship. The church is a prolific builder of temples as temples hold a key place in LDS theology. There are 139 operating temples, 1 previously dedicated but closed for renovation, 14 under construction, and 14 announced (not yet under construction). At present, there are temples in many U.S. states, as well as in many countries across the world. Several temples are at holy sites of the LDS church, such as Nauvoo, Illinois and Palmyra, New York. The importance of temples is often emphasized in weekly meetings, and regular participation in temple work is strongly encouraged of all Latter-day Saints (LDS).