I’m going to a wedding in Dorchester and would like to take the bike. Is there lots of mountain bike trails or shall i take the CX / Road bike and explore the coast?

Thanks for any advice.

Not really in Dorchester, but loads 5 miles out.
North on the A37(toward Yeovil), any of the lanes around Cerne Abbas – lots of off-road too in the area, and some real sharp hills – have a look at the OS for the area, some real tight contour lines.
The coast – great, Abbotsbury to Burton Bradstock or Lyme Regis, back on the lanes North East toward the Hardy Monument, then back to Dorchester.
Again, quite hilly in parts, and avoid the main road (A39?), as it is very busy.
CX would do the lot, but a HT is fine.

Used to pop to Puddletown woods for some cheeky, dunno if any of the trails are still there, nice and local Though.

I was riding Puddletown last weekend for the first time in a few years. Lots of short fun downhill runs, plenty of roots and sand and drops and jumps to keep things interesting. More plummet down and haul back up a fireroad than rolling singletrack but I liked it a lot.