Pancha means five and Bhootham means elements, thus Pancha Bhootha Sthalams represents the temples that are the manifestation of the five basic elements - Earth, Water, Fire, Air and Space. These five elements are believed to be enshrined in the five lingams. 

1. Prithivi Lingam at Ekambareswarar Temple

Location: Kanchipuram,Tamil Nadu

Category: Earth (Prithvi sthalam)

In this temple, Lord Shiva is said to have manifested himself in the form of Prithvi Lingam.

2. Appu Lingam (Jambu Lingam) at Jambukeshwarar Temple

Location: Thiruvanaikaval, near Trichy,Tamil Nadu

Category: Water (Appu sthalam)

Here Lord Shiva represents water and a spring gushes out water inside the Sanctum Sanctorum.

3. Agni Lingam (Jyothi Lingam) at Arunachaleswarar Temple

Location: Thiruvannamalai, Tamil Nadu

Category: Fire (Thejo sthalam)

Lord Shiva is said to have manifested himself in the form of massive column of fire.

4. Vayu Lingam at Sri Kalahastheeswarar Temple

Location: Kalahasthi, Andhra Pradesh

Category: Air (Vayu sthalam)

You can observe the lamp constantly oscillating / flickering despite the lack of air movement inside the inner sanctum of this temple

5. Aagaya Lingam (Akasha Lingam) at Thillai Natarajar Temple

Location: Chidambaram, Tamil Nadu

Category: Space (Akasa sthalam)

In this temple, empty space is worshiped as Lord Shiva (akasha lingam) to signify God is beyond human comprehension. It is unusual where there is no physical stone lingam present here.