Horizon Downloads

Caution !!! --> Please disable all download accelerators, otherwise your downloaded files will be corrupt!

Horizon 4.4 (February 1, 2008)
Horizon 4.4 Opening Book (last updated: February 1, 2008) 5% verified; verified depth ~6; 1,000 games/7,000 positions verified
Latest Horizon Opening Book (last updated: February 1, 2008)

NOTE: the download files are in 7Zip format

Test Suites

The following tests, inspired by printed chess puzzles, are maintained by Jim Monaghan

IQ Test Suite -- IQ 8.1, a tactical epd test suite (last updated: March 20, 2008)
O’Kelly Test Suite -- Combinative middlegame and endgame epd test suite (last updated: January 10, 2003)

Older Versions of Horizon

The Elo ratings are approximate. Thanks to Claude Dubois for supplying me with missing versions!

EngineElo (Blitz)
Horizon 4.32350
Horizon 4.22330
Horizon 4.12315
Horizon 4.022320
Horizon 3.312275
Horizon 3.22180
Horizon 3.12250
Horizon 2.012130
Horizon 1.22150
Horizon 1.12100

Horizon Installation and Configuration

  1. Unzip all files to the directory of your choice such as: C:\Chess\Horizon
  2. See: ReadMe.txt within the Horizon.zip file for complete Horizon instructions.
  3. Winboard.ini additions (assuming Horizon files are located in C:\Chess\Horizon):
    • "Horizon" /fd=C:\Chess\Horizon
    • "Horizon" /sd=C:\Chess\Horizon
  4. Modify the Horizon configuration file: Horizon.cfg
  • Set main hash table size to 97MB: HASH 97
  • Set pawn hash table size to 4MB: PAWN_HASH 4
  • Set egtb cache size to 4MB: EGTB_CACHE 4
  • Specify directory holding Nalimov endgame tablebases: TB_DIRECTORY C:\Chess\Nalimov
  • Specify opening book path/filename: OPENING_BOOK C:\Chess\Horizon.dat
  • Set opening book 'style' BOOK_STYLE TOURNEY 9
  • Weaken chess play (set Elo to 1543): SET_ELO 1543
  • Allow ICS on-line play ICS KIBITZ
  • Turn resignation on/off: RESIGN ON

The easiest way to verify your current configuration is to double-click on 'Horizon.exe' in Explorer. It will list the current settings. Then type 'quit' to quit the Horizon program.