The word "deula" in Oriya language refers to a building structure that adopts a undue and characteristic style that is commonly seen in most of the temples of Odisha. This style of temple architecture is native to Odisha and differs from the south Indian temples that follow the Dravidian style. With exception, one can see the Garbagraha (sanctum) in a small shrine over which there is a small tower or Gopuram. Around the Garbagraha / Srikovil one could see Prakaram(s), invariably a roof-covered passage. A deula is an element of Hindu temple architecture with special reference to Odisha. In common parlance Deula also refers to the whole place of worship.
Quite noticeable are three types of Deula: the Rekha, the Pidha Deula and the Khakhara deula. The former, also known as Bhadra houses the Garbagraha in which one can see the presiding deity and the tower - shikara over it. The Pidha Deula (pidha deul) refers to the hall or mantabam where the devotees gather. The latter is a tower in oblong shape, more or less similar to Dravidian temple architecture. It houses the entrance gate way. The difference in the case of many temples of Tamil Nadu, in particular, is the entrance towers on four sides - north, south, east and west, that are taller than the towers inside. Srirangam Ranganather temple, Madurai Meenakshi temple and Sri Villiputhur Andal (Bhoomi Devi) temple are good examples.
|Klinga temple architecture. en. wikipedia. org.|
Rekha Deula: Normally Rekha Deula is a tall tower. whose elevation is higher than the entrance tower and in the shape of a sugar loaf. It is built over the Garbagraha. In Oriya, it Deula means a straight line, here it refers to the three parts of the temple that are set in a straight line as one can see in the image included here. The tower is highly ornamental.
|Lingaraja temple,a Pidha -"shikhara deula".en.wikipedia.org|
Pidha Deula: Also called Bhadra Deula, the base of the building is square in shape with a pyramidal roof. The big hall is built for the convenience of the devotees - to worship the deity comfortably. It also includes service rooms related temple activities. It differs from the temples of Andhra, Tamil Nadu and Karnataka where the mantabam does not have a shikara over it. Some may have second mantabam at the end of which there will be Dwajasthambam - flag-staff.
|Konark Sun Temple, example of a "pitha deula" en.wikipedia.org|
|Brihadeeswarar Temple, Thanjavur.tourmyindia.com/blog|
Chola king Rajarajan in the 11th century AD. Adjacent hall/mantabam leading to the sanctum has a flat roof. This is similar to Rekha Deula of odisha.
|Srirangam Ranganather temple. Hinduism Stack Exchange|
Above image: Sri Ranganather (Vishnu) temple, Srirangam, Tiruchirapalli, TN. here the, one can the tallest tower that is the main entrance to the temple complex. This one is close to Khakara deula, but structurally different ....................
Pidha Deula differs from the temples of Andhra, Tamil Nadu and Karnataka where the mantabam does not have a shikara over it. However, many Kerala temples have a slanting or sloping roof over the worshiping area or hall, including a place for doing Namakaram - prostrating towards the direction of the deity.
|Conical roof over sactum. Madhur Temple, Kasaragod, Kerala|
|Baitala Deula example of a "khakara deula, en.wikipedia.org|
Kedar Gouri, Bhubaneswar, Narayani Temple, Khalikote (dedicated to Durga), Durga Temple, Banki, etc.
|Chengannur Mahadeva temple, Kerala.Wikipedia|
Above temple: The Mahadeva temple at Chennganur, Kerala. Here, the entrance to the temple has a sloping roof with simple design. .....
|Samayapuram Mariamman temple, TN.Trawell.in|
Above imgae: In the above image, you can see the entrance to Mariamman temple (Parasakthi) at Samayapuram, near Tiruchirapalli city, Tamil Nadu. This Goddess temple is quite popular. Note the simple entrance gate and the structure that is vastly different from Khakara deula that is characteristic of trucated low tower...............................
In Kerala, the part that is similar to Khakhara Deula that includes the entrance to the temple, has a simple design with a slanting or triangular roof or a combination of both made of wood. In Tamil Nadu, temples of great antiquity, as mentioned above, have tall entrance towers. This not so in the case of temples dedicated to Goddesses like Mariamman, Durga, Kamakshi, Kali, etc. The entrance has a simple tower with a little ornamentation.