Planar Arrangement

Inner Planes:

• Material Plane
• The Feywild/ Lunaria/ Plane of Faerie 
• The Shadowfell/ Plane of Shadow 
• Primordial Chaos
• Ethereal Plane 

Primordial Chaos:

• Plane of Fire 
• Plane of Magma 
• Plane of Earth 
• Plane of Ooze 
• Plane of Water 
• Plane of Ice 
• Plane of Air 
• Plane of Ash 

Outer Planes:
Outside exists the Astral Plane , a great sea of shimmering silver; streaked with swirling wisps of white and gray, amongst which numerous planes drift.
Upper Planes:

• The Seven Heavens of Mount Celestia 
• The Peaceable Kingdoms of Arcadia 
• The Twin Paradises of Bytopia 
• The Blessed Fields of Elysium 
• The Wilderness of the Beastlands 
• The Olympian Glades of Arborea 
• The Heroic Domains of Ysgard 
  

Lower Planes:

• The Windswept Depths of Pandemonium 
• The Tarterian Depths of Carceri 
• The Grey Wastes of Hades 
• The Bleak Eternity of Gehenna 
• The Infinite Layers of the Abyss 
• The Infinite Battlefield of Acheron
• The Nine Hells  
  

Plane of Law:

• The Clockwork Nirvana of Mechanus 
  

Plane of Chaos:

• The Ever-Changing Chaos of Limbo 
  

Belaying all existing planar maps, it has been gleaned from several contracted devils that there exists a sort of stairwell between all planes, with rare entryways either zealously guarded, carefully hidden, or yet undiscovered...

The Five Planar Rivers:

• The River of Woe, Acheron 
• The River of Lamentation, Cocytus 
• The River of Fire, Phlegathon 
• The River of Unbreakable Oath, Styx 
• The River of Memory and Oblivion, Lethe