Why did you decide to redevelop Longleat, the safari and adventure park?
We approached architecture and design firm Forrec following a period of substantial growth here at Longleat. Attendance has increased more than 25 per cent over the past couple of years and that has started to have an impact on infrastructure and the guest experience. Forrec has created a 10-year masterplan to address parking lots, toilets, restaurant and retail capacity, transportation, entry points and way finding.

We’ll work with Forrec on a strategy to phase in the upgrades, so I don’t have an overall budget figure for the masterplan. We might spend £2m to £3m ($2.9m to $4.3m, €2.5m to €3.8m) some years, but we don’t plan to do that every year.

How did you achieve this growth in attendance?
We are doing a lot of things better. We’ve introduced a Chinese-style lantern festival that has been a big boon to our business. In 2015, our figures were up every month. We’ve built a stronger team, we’re marketing better, we’re gathering better data that allows us to be more targeted.

Our guest scores are higher than they’ve ever been. We measure that pretty rigorously using the Net Promoter Score methodology, which is the strongest indicator we have that the guests’ intention to come back is really high. The percentage of visitors who would recommend us to a friend is up in the 90s – those are world-class guest scores.

I wish I could tell you that we’re doing something clever, but it’s the fundamentals. We strengthened our leadership teams and increased our staff rates. We also set up a profit-sharing scheme for staff. It makes a difference when staff buy into what we’re doing and are proud of the product.

Aside from infrastructure, what other changes are planned?
Authenticity is one of our core values. It was increasingly difficult to marry a safari theme with our desire to be sympathetic to the site’s heritage. We started to think differently about theming. Our lions are on green grass surrounded by oak trees, so why not be more honest about that.

So you’d like to tell a story that is closer to Longleat’s history?
Yes, a story that’s grounded in an authentic base. There have been exotic animals throughout Longleat House’s 400-year history. It was a menagerie. People gave exotic creatures as gifts. In the archives, we have letters written by the owner begging not to be gifted any more tigers.

We have this real tradition and animals are part of his eclectic collection that ties together the house, the exhibits and the attractions. We love this idea and it will be a differentiator in terms of the way we think. It’s also a new way of thinking about what attractions we want to introduce, how we change the look and feel of the park or how we repurpose existing attractions.

What challenges did you face?
As Longleat is a heritage-status property, including the safari park, buildings and 900-acre (364-hectare) grounds, Forrec’s blueprint has considered – from the start – potential planning issues, which pose a significant challenge for us. It should make it easier to gain the approval of Historic England, Natural England and other bodies.

What can we look forward to in the the near future?
We have some great animal additions coming next year. We like the idea of mixed exhibits; for example, wolves and bears live really well together. Multi-animal habitats add depth and richness to the experience.

We’re about to open a 9,000sq ft (836sqm) freespan building called The Longhouse. It’s a multi-use building for temporary exhibits, theatrical productions and catered events. It allows us to bring in unique programming all year long without having to go through the hoops of planning consent and approvals that used to take so long – and that’s a tool for us to do more event-based activities.

How are you celebrating the 50th anniversary?
We are having an African summer with performers, dancers and acrobats, as well as an evening parade.

This year sees the introduction of our hot air balloon festival. Over a three-day period more than 50 hot air balloons will be drifting over the estate between sunrise and sunset. We also have an outdoor concert headlined by Sir Elton John in June, the first music concert held at the attraction since the Rolling Stones played in the 1960s.

Aren’t there rumours you could host Glastonbury Festival in 2018?
We have sold all 15,000 tickets for the Elton John concert, but there’s a big difference between doing this and doing a music festival. It’s a step for us: if we can do a show like that once or twice a year, that’ll maybe open up other options for us.

What other events have been successful?
The Festival of Light began in 2014 as a Christmas festival combined with a Chinese lantern festival, with thousands of lanterns. It was hugely successful. We repeated it in 2015 and achieved growth of 20 per cent and the best guest scores we’ve ever had.

The Festival of Light helped us to establish that we can be an event centre, not just a safari park. By expanding our events we see great results: our Christmas period was as strong as our summer.

For 2016, we’re partnering Beatrix Potter for the lantern festival. It’s the author’s 150th birthday and our 50th – two quintessential British brands. Our light display is going to be Peter Rabbit and Mr McGregor’s Garden, with installations up to 60 feet (18 metres) tall.