- Venue: Cheltenham Racecourse
- Dates: 12-15 March
- First race: 14:05 GMT
Coverage: Commentary on every race on BBC Radio 5 live or 5 live sports extra from 13:30 GMT (also available online and on mobile devices). Daily live text commentary from 12:30 GMT on BBC Sport website
The opening day of the Cheltenham Festival has gone ahead despite overnight frost, but the start of racing was delayed by 35 minutes.
The first race went off at 14:05 GMT and the Champion Hurdle, the day's main race, was put back to 16:00.
But the Cross-Country Chase, pencilled in for 17:45, will now run on Thursday at 17:15 after an inspection.
"Temperatures fell to -4C last night so a hard frost formed as expected. It's going to be a pretty cloudy afternoon although the sun may break through the clouds at times to give a few sunny spells. Although the cloud may be thick enough to give a very light wintry flurry, it'll stay mostly dry with a maximum temperature of 3C. However, with a brisk north-easterly wind it'll feel more like freezing or below!
Another frost is expected tonight with temperatures falling to -2C by Wednesday morning. Bright spells are expected but there is a greater chance of perhaps the odd light wintry flurry on Wednesday afternoon with a maximum temperature of 5C."
That means the opening day programme has been reduced to six races, from the seven originally scheduled.
The course has been protected by frost covers with temperatures feeling as low as -11C with the wind chill factor.
Course spokesman Andy Clifton told the BBC: "Around 95% of the track is absolutely fine under the covers, there are just one or two areas that are causing a small amount of concern.
"The frost covers do their job so where they haven't been, it will be pretty cold."
An estimated 230,000 spectators are expected over the four days.
Frost covers went down at the weekend on the old course track, which is used for the first two days, and the new course - which stages racing on the final two days.
The tarpaulin-style covers - across an area of about 65 acres, or the equivalent of 45 football pitches - were lifted on the old course this morning.
REVISED DAY ONE SCHEDULE
2.05 William Hill Supreme Novices' Hurdle (Grade One) 2m 110y £120,000
2.40 Racing Post Arkle Challenge Trophy Chase (Grade One) 2m £150,000
3.20 JLT Specialty Chase (Handicap) (Grade Three) 3m 110y £90,000
4.00 Stan James Champion Hurdle (Grade One) 2m 110y £400,000
4.40 OLBG Mares' Hurdle (Grade Two) 2m 4f £85,000
5.15 Pulteney Land Investments Novices' Handicap Chase (Listed) 2m 4f 110y £60,000