A Milling Milestone opens on 18 September and runs to 29 November. It costs £6.25 for adults, £2.10 for children, and there are only 22 opening days.
The watermill at Mill Green stopped grinding flour in 1911 and sat idle for most of a century. It has been working again for 40 years, and the borough’s museum service is marking that with an exhibition opening on Friday 18 September.
A Milling Milestone runs until Sunday 29 November 2026, which is the last day of the museum’s season. It is not on for long, and the museum only opens two days a week, so the practical number is this: there are 22 opening days in the whole run.
Entry costs £6.25 for an adult and £2.10 for a child aged 2 to 16, and that is the same as ordinary admission. The exhibition is included rather than charged for separately. Those prices were checked against the museum’s own booking system on 13 September.
What is in it
The exhibition covers the mill from its origins to the people running it now. Welwyn Hatfield Borough Council’s announcement says it traces the mill’s history “from its origins in the late 11th century, with its mention in the Domesday Book, to its restoration, looking at the people and craftsmanship who made it possible and how they keep it running today”.
The restoration is the anniversary being marked, and the council’s account of it is specific. Work began in 1979, carried out by members of the Hatfield and District Archaeological Society and Millwrights International Limited. It involved replacing rotten joists and floorboards, repairing brickwork, and getting water flowing from the River Lea to the mill again. The final phase replaced the mill machinery and built and installed a new water wheel. The mill was restored in 1986 and has milled ever since.
Before that, the council says, the mill had been in regular use “for at least eight hundred years until it ceased operating in 1911”.
Councillor Max Holloway, Executive Member for Community and Leisure, called the mill “a piece of medieval history that through the hard work and ingenuity of some brilliant local experts, has been restored to its former glory”.
One point of precision worth having before you go: the building you walk into is eighteenth century. The museum describes it as an “18th Century restored working watermill” that “harnesses the power of the river Lea to grind grain into flour and is part of a 1,000 year history of milling on this site”. The Domesday entry is about milling at Mill Green, not about the standing building.
Going: the details that decide whether you get in
The museum works on timed entry, and the sessions are small.
- Open Fridays and Sundays only, 10am to 4pm
- Sessions start at 10am, 11am, 1pm, 2pm and 3pm. There is no midday session
- 30 places per session
- Tickets include the museum galleries and the mill itself
- The site is cashless, and takes card payments only
- Parking, including accessible bays, is on site
Mill Green Museum and Watermill is at Mill Green, Bush Hall Lane, Hatfield AL9 5PD, just off the A414 between Hatfield and Hertford. The museum says it is a 15 minute walk from Hatfield station, and that buses from St Albans, Welwyn Garden City, Luton, Broxbourne and Waltham Cross stop nearby.
One thing that catches people out. The borough runs two museums, and they are never open on the same day: Mill Green takes Fridays and Sundays, while Welwyn Roman Baths takes Saturdays. The 301 bus runs between them. We set out both in our guide to things to do in Welwyn Garden City.
Book through the museum’s own general admission page.
What it means for you
If you want to see it, the calendar is the constraint rather than the price. Twenty-two opening days between 18 September and 29 November, five sessions a day, 30 places a session. Half-term and the run-up to Christmas will be the busy part, and the museum closes for the winter on 29 November and does not reopen until 5 March 2027.
The other dates to know are Friday 30 and Saturday 31 October, when the museum runs The Miller’s Monster Mash Bash. That is a separate ticketed event at £10 a head, free for children aged 2 and under, with hourly sessions from 10am to 2pm on both days. The Saturday is worth noting because the museum does not normally open on Saturdays at all.
Frequently asked questions
How much does the Mill Green exhibition cost?
£6.25 for an adult and £2.10 for a child aged 2 to 16. That is the museum’s standard admission price, and it covers the galleries, the working mill and the exhibition. The site takes card payments only.
When is Mill Green Museum open?
Fridays and Sundays, 10am to 4pm, with timed entry at 10am, 11am, 1pm, 2pm and 3pm. The season ends on 29 November 2026 and the museum reopens on 5 March 2027.
Do I need to book ahead?
Yes, in practice. Entry is by timed session and each session holds 30 people, so walking up is a gamble, particularly at half term. Book on the museum’s general admission page.
Sources
- New exhibition opens at Mill Green Museum and Watermill, Welwyn Hatfield Borough Council, 7 September 2026, for the opening and closing dates, the restoration history, the 1911 closure and the quotation from Councillor Max Holloway.
- A Milling Milestone, Mill Green Museum and Watermill, for the exhibition listing and the note that tickets include entrance to the museum and mill.
- Mill Green Museum and Watermill general admission, for the Friday and Sunday opening, the 10am to 4pm hours, the session times and the ticket prices, checked 13 September 2026.
- Visit Us and About the Mill, Mill Green Museum and Watermill, for the address, the travel directions, the cashless policy, the season and reopening dates, and the description of the building as eighteenth century.
- What’s on at Mill Green, for The Miller’s Monster Mash Bash dates, session times and price, checked 13 September 2026.
Have your say