If you like a bit of challenge with your mountain biking, and you haven’t been lately to the Yudicky Fields and Lovewell Pond trails, it’s time for another visit.

For one, the field around the old dirt bike track is in glorious bloom, and better yet, the trail-smiths of the New England Mountain Bike Association have cut a whole new and demonically twisted section of singletrack in the Lovewell Pond area. The new section, dubbed Fireball, includes more climbs, descents and sphincter-puckering obstacles… a few of which aren’t quite finished, so look before you lunge.

The Nashua River Rail Trail lot off Gilson Road or the athletic fields at the junction of Gregg and Main Dunstable Roads are your best bet for parking, if you can’t ride there.