Arcane Secret

As you cast the spell, you draw a 10-foot-diameter arcane circle on the ground. Once you enter the circle a shimmering seal surrounds the circle you drew like the lid of a Bell Jar. No creature may enter the Circle or hear anything happening inside the circle once you have entered. You also are unable to be located by any spell or magical item while inside the circle (unless you wish to be). The spell ends after ten minutes, you lose concentration on it, or you chose to drop the spell early. Until the spell ends no one can leave the circle.

AT HIGHER LEVELS: When you cast this spell using a spell slot of 6th level or higher, the duration increases by 10 minutes for each slot level above 5th.

You can create a permanent Arcane Secret circle by casting the spell utilizing rare Liquid Platinum Infused with Precious Gems worth 18,250 gp in place of the chalk and ink, then casting Mending which gets amplified by the gems inside the platinum to set the circle permanently. A circle set this way does not require material components or a spell slot to utilize.