Where is Pitru Loka among the 14 lokas?

Question

My dear son Nārada, know from me that there are seven lower planetary systems out of the total fourteen. The first planetary system, known as Atala, is situated on the waist; the second, Vitala, is situated on the thighs; the third, Sutala, on the knees; the fourth, Talātala, on the shanks; the fifth, Mahātala, on the ankles; the sixth, Rasātala, on the upper portion of the feet; and the seventh, Pātāla, on the soles of the feet. Thus the virāṭ form of the Lord is full of all planetary systems. (Srimad Bhagavatam 2:5:40-41)

The universe is divided into fourteen planetary systems. Seven planetary systems, called Bhūr, Bhuvar, Svar, Mahar, Janas, Tapas and Satya, are upward planetary systems, one above the other. There are also seven planetary systems downward, known as Atala, Vitala, Sutala, Talātala, Mahātala, Rasātala and Pātāla, gradually, one below the other.

Pitr are souls of those who are deceased from the family. Where is Pitra loka situated?

How are Pitr related to Pitr loka? When do they come here? For how much time do they stay in Pitr loka?

Answer 1

The verse in the question briefs about the Bila-auspicious planetary system (7 Bila-swarga from waist to feet of the Lord). Below which is Pitra Loka. Lord Vishnuji is sitting on the Shyam rang (Dark Matter) ocean-- is nothing but Garbhodaka Ocean on which cosmic Vishnu rests over SheshNag. Shesha is said to uphold all these parallel auspicious, Bila-auspicious Universes, naraka universes on his hoods and constantly sings the glories of the God Vishnu from all his mouths. He is sometimes referred to as Ananta Shesha which translates as endless-Shesha or Adishasha "first Shesha". Now, below Pitra Loka and just slightly above this Garbhodak ocean resides the suffering universes --7 narakas which Lord Vishnuji usually doesn't casts his special mercy, grace until the time jivas therein sufferring due to evil past deeds, till stipulated suffering duration ends up.

Vishnu purana described as below: Planets from Satya loka to earth(Swarga-Loka) and lower swarga : planets that do not need the Sun for survival (Bila-Swarga). Below the lowest Bila-swarga planet of Pataal, is the planet of the Manes or ancestors who are known as the >Pitras.

Beneath all these, and slightly above the Garbhodak ocean, are the Naraklokas, or the hellish planets.

So, Pitra loka is spatially between the 14 swarga(7-swarga,7-bila swarga) and naraka(hellish abode)

Note: The visible world we understand is 3-Dimensional, while one needs YOGIC vision to experience 4th dimensional reality and beyond to have better perceptions about these worlds.

Very important day each year to worship pitra: Mahalaya amavasya(also known as Sarvapitri Amavasya) falling on September 17,2020 this year, following rites properly which helps pitra's step further towards moksha siddhi and descendents free from karmic Pitra dosha due to bad, immature illicit deeds in lifetime which are against the ancestral principles.