Richard Reti (1889--1929) composed a number of great endgame studies. Here are two of my favorite pawn endgame studies.

The following study is perhaps his most famous, beautiful in its simplicity.

Reti, Richard    --    Study
Kagan's Neueste Schachnachrichten   1921     1/2-1/2



White to move.


1.Kg7 h4

( 1...Kb6 2.Kf6 h4 3.Ke5 h3 4.Kd6 h2 5.c7 = )
2.Kf6 Kb6
( 2...h3 3.Ke6 = )
3.Ke5 1/2-1/2

The study below was dedicated to Julius Breyer, and is based on coordinate squares theory.

Reti, Richard    --    Study
Berliner Tageblatt   1923     1-0



White to move.


1.Kg5!

( 1.Kg6 Ke7 2.Kf5
( 2.g5 d5 3.Kh7 d4 4.g6 d3 5.g7 d2 6.g8=Q d1=Q = )
2...Kf7 3.Ke4 Kg6 4.Kd5 Kg5 5.Kxd6 Kxg4 6.Kc5 Kf5 7.Kb5 Ke6 8.Kxa5 Kd7 9.Kb6 Kc8 = )
1...Kf7
( 1...Ke7 2.Kg6! wins as below. )
2.Kf5 Ke7 3.Kg6 (zugzwang) 3...Ke6
( 3...d5 4.Kf5 Kd6 5.g5 +- )
4.g5 1-0