Well, you didn't grep hard enough; I just did: grep '[.H][0-9]' /usr/share/lib/zoneinfo/usno1989 And got 11 part-hour zones, 3 of which apply DST which can be also counted as separate timezones; plus Russia's East Siberia zone which is 13 hours ahead of GMT and 14 with DST. In total, we have 24+12+4 or 40 time zones, 36 of which are in use somewhere at any given time. Amos Shapir Net: amos@cs.huji.ac.il Paper: The Hebrew Univ. of Jerusalem, Dept. of Comp. Science. Givat-Ram, Jerusalem 91904, Israel Tel: +972 2 585706 GEO: 35 11 46 E / 31 46 21 N