Ruined portals are the cheapest early nether access there is, and their chests carry obsidian, flint and steel, gold and the occasional enchanted pickaxe. The map plots them so a fresh world can be in the nether within minutes.

• The chest matters more than the portal frame — even a portal too broken to light is worth the walk for the loot.
• Missing obsidian blocks can be filled in by hand, so a ruined portal near spawn is effectively a free nether trip.