I've only been to 20 or so sites this year, having a baby eats away your spare time, who knew?! As such my choices are limited, so I'll go for Gardom's Edge, in particular the enclosure.

I'm a sucker for large neolithic monuments...

10) Wallbury, Essex - you mean Essex has hillforts? Er, yes...
9) Fairmile long barrow - I thought I'd seen them all. Wrong.
8) South Ythsie.... glorious stone circle.
7) Had a bit of a fixation with wooded hillforts this year.... the way in which nature has attempted - and in some cases suceeded - in reclaiming them. A particular challenge trying to capture variance in light and shade. Ring Hill, near Saffron Walden, as good as any.
6) Tap o'Noth.... truly primeval experience blown all about these great ramparts during the high winds of May.
5) Tinto cairn...... outstanding
4) Carn Lliath long cairn, Tain - the perfect forest vibe.
3) Coetan Arthur, St David's Head - location, location, location.
2) Y Garn, Nantlle Ridge - two monster cairns where you would least expect.
1) Carnedd Llewelyn/Foel Grach.... mind blowing that these monuments still exist in such locations. A brocken spectre to boot.

This year I have been lucky enough to have had a fair old pile of stays down in Galloway and lots of time to visit and re-visit sites there.
My favourites were many! I think actually finding the beautiful posy of three fine stemmed blossoms at Torrs 2 was my year highlight. I had water and the sun broke through the clouds just in time for a nice phoatie. A friendly, helpful farmer sweetened the visit even more.
I also found myself on the Doon of Carsluith in the very early morning one day in July looking across the Solway to the Isle of Man as it sat hovering on a haze of fog fifty miles away in the grey morning light. Very beautiful and haunting.
Over the course of a few visits I got the chance to explore the Barharrow sites. I even found a new panel. I tried many times to get a decent photo of Barharrow 8 and failed. There was a herd of very frisky black Galloway Bullocks in the Barharrow 8 field and I had to try and sneak in without them seeing me, frame a couple of shots in plain view of the frisky beasts then leg it outta the field as they charged. Each time I got back to our holiday digs I'd check my photos and find them blurred or rubbishly framed. I'd then return and try again. On the last attempt I fled the field after getting a few shots and looked back only to find the bullocks gathered round the rock outcrop staring at it as if to say "Why's that weird guy so interested in this bit of rock".
In October we were back in Galloway and staying in a beautiful cottage a few hundred yards from Trusty's Hillfort. Beautiful Pictish carvings. I found a large "new" cup marked panel. The Townhead rock art was a fabulous muddy October walk, again assisted by a helpful farmer on his quad. Followed by a gourmet fish supper from the fish and chip shop by the harbour in Kirkudbright. Oh yes!
My summer week in Arran was the usual seven days in heaven, ancient stones and sites at every turn, some "new" ancient sites were explored at Allt Cul Corrieham beyond the exotically named Teanga Burrican. Stronach Wood is still an evolving marvel... there's a stag now... don't get me started!
Roll on 2012!

Spending a week in Cumbria back in May, all quite an intense experience - my much loved Mum had died a three weeks earlier.

As said in my previous reply I fell totally in love with Castlerigg even though first seen in the pouring rain. Later in the week we made the long drive down to south Cumbria to visit Swinside which I had read was on a par with Castlerigg as surrounded by (albeit less dramatic) fells. My friend, doing the driving, was a keen walker, whereas I just wanted to get to Swinside. Shared holidays are about accommodating each others interests so I readily agreed to the five mile walk my friend had planned - which in theory would take us across Swinside Fell to the circle.

We parked in a village on the road to Millom and set off. Friend was however using an old 1960s one inch map, a big mistake as it transpired; after crossing the A5093 (a fast road) we walked downhill towards the astonishing site of a reservoir being 'restored to nature' - workman and diggers moving tons of earth around. Before too long we were hopelessly lost and to make matters worse we had just picked our way through a bog only to find ourselves hemmed in by barbed wire fencing. My feet were wet but we had no alternative other than walk back through the bog retracing our steps. My friend was now hungry and wanted to abandon the whole project in favour of food but I was determined - "lets just try the turning for Broadgate" ... we did and found a clear signpost up a single track road to the circle.

Car parked and a walk of about a mile up the track across open fenland with just cattle for company. By now completely chilled due to soaking wet feet and a cold wind blowing - this visit stands out as my most uncomfortable but thoroughly worthwhile. Its a beautiful, perfect and remote stone circle - with a fairly strong possibility of having it to yourself. Just don't do it the hard way.

For the sense of achievement I felt and the sheer joy of reaching the top, the walk up Drum with The Sweet Cheat.

I was hoping to see Moth and/or Jane's answer to this question.

:o)

Oh well, here's mine:

Looking back, it was a rock arty year for me.

I became one of the volunteers on the CSI: Rombalds Moor rock art recording project, which should keep me busy for the next year.

On these Isles, I eventually got to see Ormaig at the third attempt at trying. Even then, my luck was in as there were a lot of logging operations going on in the area and even at Ormaig itself the trees were coming down.

http://www.themodernantiquarian.com/post/62347/ormaig.html

I must confess, I've fallen in love with the American Southwest; its deserts, canyons, mountains and wilderness. This year, amongst many sites visited, I got to the cliff dwellings of Mesa Verde and the pueblos of Chaco Canyon. However, my "best site visited in 2011", without doubt, is the rock art within Horseshoe Canyon. It took careful planning to get to, as the rim of the canyon is a 30 mile drive on a sand road across the San Rafael Desert, the floor is 830 feet below the rim and the main panel of rock art, the Great Gallery, is a 6.5 mile round trip along the bottom of the canyon.

http://en.wikipedia.org/wiki/Mesa_Verde_National_Park
http://en.wikipedia.org/wiki/Chaco_Culture_National_Historical_Park
http://www.utah.com/nationalparks/canyonlands/horseshoe_canyon.htm