Welcome to the Final Four of Monument Madness, The Washington Post's challenge to see which of the region's monuments stands above the rest. Here's a look back at what happened in a very unpredictable Round of 16 and Elite 8.

(2) Lincoln Memorial 522, (1) Washington Monument 210.
(6) National Seabee Memorial 683, (1) U.S. Marine Corps War Memorial 326.
(4) Jim Henson and Kermit statue 547, (7) Dante Alighieri statue 199.
(7) National Fire Dog Monument 691, (1) Second Division Memorial 238.

Underdogs? What underdogs? Top seeds continued to fall -- hard -- as the Washington Monument, U.S. Marine Corps War Memorial and Second Division Memorial were all emphatically bounced in the Elite 8, while one of the tournament's most obstinate, hardship-hardened contestants was drubbed by a singing frog. Who knows what will happen in the final four?

The matchups that follow are the tournament’s Final Four. Polls are now closed. Voting for the championship round is open through Monday

(2) Lincoln Memorial vs. (6) National Seabee Memorial

The Washington Monument proved no match for Lincoln, who put forth an honest effort in toppling the convalescing obelisk in the Elite 8's marquee matchup. Meanwhile, the unheralded Seabees surprised the Marines, living up to their "Can Do" mantra in building a convincing upset against a top seed. So here we are: the Rail Splitter vs. shipyard builders; a long, lean Kentuckian vs. muscle-bound might. It's Lincoln vs. the Seabees for a spot in the Monument Madness title matchup.

(4) Jim Henson and Kermit the Frog statue vs. (7) National Fire Dog Monument

The top-seeded Second Division Memorial had good reason to fear the seventh-seed National Fire Dog Monument: After all, if there was anyone in this field capable of outmaneuvering a giant flaming sword, it was a canine who sniffs out fires for a living. Sadie knew exactly how to exploit the sword's weaknesses and did so to dominating effect. The fire dog's semifinal opponents have proven fearless so far: After outsmarting Einstein in the Sweet 16, Henson and Kermit pulled off another Great Muppet Caper to win a laugher that practically gives new meaning to "The Divine Comedy."