Logic Masters Deutschland e.V.

This is my third puzzle themed on my home city of Washington, DC. I've previously set puzzles based on the DC Metro and the DC flag. This time, I'm working off the city's map. The title is, of course, aspirational.

Normal sudoku rules apply.

Anti-King: As befits the capital of a nation that rejected monarchy, diagonally adjacent cells may not contain the same digit.

Skyscrapers: Each digit in the grid represents the height of a building in its cell. Taller buildings obstruct the view of shorter ones behind them. Clues outside the grid give the number of buildings visible from that vantage point in the clue's row or column.

Dutch Whispers: Along the orange border, adjacent digits must differ by at least 4.

Region Sum Lines: The sum of digits along the blue rivers must be the same in each 3x3 box they pass through.

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