Related Clues:

• Mark boundaries of shop with German
• Check breaking point
• Learning? This setter's the one to check
• Frontier this writer's established in literature
• Maximum road speed
• End, as of one's patience
• Fruit cut, it follows, producing edge
• Landed outside one mile boundary
• I'm passing through illuminated border
• Left motorway during Italian restriction
• The sky, in a saying
• Maximum raise in poker
• Allowable extreme
• Point beyond which one should not go
• The sky's the ___