What year was the modern Swiss Federal Constitution adopted, creating today's federal state?

1848 → dove · roof.

The 1848 Federal Constitution followed the brief Sonderbund War of 1847, in which the liberal Protestant majority defeated a separatist league of conservative Catholic cantons. Borrowing partly from the U.S. model, it turned a loose alliance of sovereign states into a modern federal state: a bicameral parliament, a federal government seated in Bern, a single currency (the Swiss franc, from 1850), one internal market and army — while leaving the cantons broad autonomy. It is the foundation of the Switzerland of today. Peg 18 · 48 → dove · roof: a dove nesting on a roof.

Tip: This is the single most important date in modern Swiss statehood.

Go deeper:

• Swiss Federal Constitution — Wikipedia — the 1848 document that created the modern federal state.
• Sonderbund War — Wikipedia — the 1847 civil war whose outcome produced that constitution.