Allerton Park and Retreat Center Location xxx515 Old Timber RdMonticelloIL61856 Next Event Allerton Trail Glo Friday Night 5K - Allerton Trails Half Marathon & 10K - 21 Apr 2023 - 20:30 Loading Map.... Allerton Park and Retreat Center515 Old Timber Rd - Monticello 40.0035318 -88.65110709999999 Upcoming Events Allerton Trail Glo Friday Night 5K - Allerton Trails Half Marathon & 10K - April 21, 2023 - 8:30 pm