Richard had told me about the Tongariro Crossing, which the guide books describe as the best one-day hike in New Zealand. It's a six to seven hour walk up and around two active volcanic mountains - Ngauruhoe (Mount Doom in the Lord of the Rings films), and Tongariro.

Neither of us have walked for that length of time before and we didn't have proper hiking boots so Richard was quite reluctant. However, the more I read about what you saw on the walk the more I really wanted to do it, even if it was on my own.

We booked into the campsite near the start of the walk at Whakapapa in Tongariro National Park. Just after Richard had decided he would do the crossing we were sat drinking a cup of tea when a German girl came hobbling past with blisters on her feet and told us she'd just finished the walk. Oh dear! However, we didn't back out and stuck to our plan of doing it the next day because the weather forecast was good.

I didn't sleep that well the night before worrying whether my knee would be ok as it had starting hurting again after a short run I'd made the previous day at the dam. I was also hoping Richard wouldn't twist his ankle having decided to wear his trainers rather than hire hiking boots and risk getting blisters.

As it's a one way walk you have to get a bus to drop you off at the start and pick you up at the end. The buses go at 7am, 8am and 9am, and we chose the middle one. The driver got everyone to fill in a form giving name, age, vehicle registration etc - so that if you didn't make it to the last pick-up time (5pm) then alarm bells would start ringing. As we filled in the form, we noticed that one couple were both aged 72!

After the bus dropped us off, we started the 20km walk along with the hundreds of other people who make the trip each day. We followed everyone else like lemmings, stopping more than we normally do to try to pace ourselves and drinking lots of water like we'd been advised. Richard was a true gentleman and carried my share of the water (four litres in total) so my pack was lighter with just sandwiches and a jumper in. (He would like to point out that his weighed nearly a stone at the start of the trek.)

Twenty minutes into the journey people started to stop and take off their coats and fleeces. Against all advice we'd gambled on the weather staying fine and not taken jackets with us. We passed one poor girl already panting. She didn't look like she could walk to the end of the street and needless to say we didn't see her again.

We spent the first hour walking up a gentle hill to Soda Springs and then started a steep climb past the old lava flows up to the yellow crater. The path was well defined with steps built in to make it easier. We stopped to catch our breath for a couple of minutes and got talking to a lovely old couple we'd previously overtaken. The guy apologised for his wife being slow and went on to the explain she'd had two hip replacements!

As we reached the yellow crater at the top of this section we looked out and could see Mount Taranaki, which is about 60 miles away on the west coast. The sky was crystal clear - we later found out this was rare and due to strong southerly winds on the previous few days.

The flatness of the yellow crater was a much needed relief on the thighs. The floor was a sandy soil texture with clumps of pale grass dotted around. The effect was almost moon like. This area was the closest point to Mount Ngauruhoe. We could see speckles of colour moving on the mountain, these were people mad or brave enough (take your pick) to climb it. We saw a young couple starting their ascent. The girl was wearing a skimpy vest top and trainers, not the sort of gear you'd think would be appropriate to climb a 45 degree mountain. Safely to say with our inadequate outfits we weren't doing this three hour return optional extra, so carried onto the red crater.

Having been concerned about our footwear for the crossing we certainly had nothing to worry about. The route is well trodden and we didn't look out of place. We saw at least two people wearing the traditional style Converse trainers which I know from my experience are not the comfiest or most supportive. Although we did hear that someone had completed the trek in a pair of flip flops!

We walked along the edge of the red crater which is a lovely crimson colour and has interesting shapes formed inside. From here we walked up a ridge to the highest point where there were spectacular 360 degree views. The scenery was so good it looked like it couldn't be real, it felt like someone had designed it. We were now half way into the walk and I was quite surprised that my legs felt as good as when we started.

The only problem was we couldn't work out where the next part of the route was as it felt like we were at a dead end. The ridge just seemed to disappear into thin air. Richard asked a woman the way and she pointed back over her shoulder and said "That way, straight down!". Richard wasn't too keen on this as he wasn't happy standing on the ridge even though it was 15 feet wide. I went to investigate and sure enough the woman was right. We had to negotiate a slope of loose scree that was steep as a black ski run. Luckily the scree helped act as a brake as we could dig our feet in. Memories of Rotorua came flooding back as there was an eggy smell in the air from the steaming vents in the area. I felt a little bit hungry but not surprisingly couldn't face eating my egg sandwiches!

At the bottom were three emerald coloured pools which we wandered around and then continued along a flat barren looking area. As we looked back we got treated to a spectacular view of the crimson red crater, the slope we'd just walked down, and Mount Ngauruhoe with Mount Ruapehu hiding behind. It was the icing on the cake to top a superb day.

We still hadn't finished yet though. There was a small climb up to the blue lake where people were sitting around eating lunch and drinking water. I think I'd drank more than I was sweating out as I wanted to go to the toilet. Rather than take my second layer off in the heat I kept it on in the hope of sweating it out.

From the blue lake it was pretty much down hill with views across Lake Taupo in the distance. We walked down the twindling pathways and then through the forest. This was the least impressive part of the walk as we've walked through plenty of forests in New Zealand plus it was slightly ruined by the constant sound of a helicopter delivering materials to work being carried out on the pathways.

We made it to the end in 6 hours and 10 minutes and were the only ones from the 7am, 8am, and 9am buses to get back for the first pick up.

The whole day had been amazing and we are both extremely pleased we did it. It far outweighs everything else we've seen over the last four months in New Zealand and beats other natural wonders around the world that I've been to such as the Grand Canyon and Monument Valley. I just hope that when I'm in my 70's or have had a double hip replacement that I can still do it again!

Katy