Adventurous ideas for DH's birthday

[whoknows1230]

DH is 40 early next year and I'm stuck on a birthday present for him. He likes adventurous things but has done a parachute jump, driving fast cars, paragliding, bungee jumping etc. Has anyone got any other ideas? We're near Birmingham but happy to travel, possibly even abroad for a weekend if I can organise a babysitter.

Driving a tank experience. Or a HGV.
Hot air balloon trip.
Flying in a wind tunnel. Available at Xscape in Milton Keynes, and probably lots of other places!
Trip tp GoApe!
Zoo keeper for a day type thing, to include feeding the lions.
Walking over the O2 Arena in London.
Absailing.

Gorge walking/ canyoning. I thoroughly recommend crags adventures up in the lakes, make a weekend of it. It's great fun. DH and I have done most the things you list, but gorge walking holds a special place in our hearts. Its refreshing, enjoyable and adreneline fuelled but takes a few hours to complete so seems better in lots of ways.

We have walked wolves and gone llama trekking!