![The clear waters of river Mimram on a sunny day, there are water plants in the river and there is vegetation on the banks. In the background is a meadow extending into the distance and a couple of trees against a blue sky.](/sites/default/files/styles/node_hero_default/public/2023-08/Archers%20Green%201.jpg?h=07ba4321&itok=mdxYpGBu)
The River Mimram at Archer's Green - one of just 240 chalk streams worldwide.
![Birdseye view of Archer's Green nature reserve: the river Mimram can be seen horizontally bisecting the photo, in the bottom half is a green meadow, the top half is dry brown grass. The banks of the river are greenest and there are trees dotted along its length.](/sites/default/files/styles/node_hero_default/public/2023-08/Archers%20Green_0.jpg?h=612f06e7&itok=LeozOalL)
Birdseye view of Archer's Green and the River Mimram
![The clear waters of the River Mimram, reflecting the dappled sunlight and revealing the pebble strewn river bed below the surface. Its banks are lush with green vegetation and to the right a tree hangs over the water.](/sites/default/files/styles/node_hero_default/public/2023-10/River%20Mimram%20at%20Archers%20Green%20%28c%29%20Debbie%20Bigg.jpg?h=81a3771e&itok=8YJNHr3u)
River Mimram at Archers Green © Debbie Bigg
![A wildflower meadow edged with trees extending into the distance.](/sites/default/files/styles/node_hero_default/public/2023-10/Grassland_Archers%20Green%20%28c%29%20Debbie%20Bigg.jpg?h=81a3771e&itok=Vps7-rHN)
Archers Green Nature Reserve © Debbie Bigg
Archer's Green
Know before you go
Dogs
When to visit
Opening times
Open at all timesBest time to visit
All year roundAbout the reserve
An idyllic section of the Mimram Valley containing a stretch of an internationally important chalk stream, flower-rich meadows and marginal wetland. Archers Green Nature Reserve consists primarily of lowland grassland home to rare Wildflowers and Butterflies adjacent to the River Mimram where you can find Water Voles, Brown Trout and Dragonflies.
Strategic importance
Archers Green sits in the Mimram Valley, a priority area for conservation action in Hertfordshire. The land is connected to other sites of importance for wildlife, adjacent to Panshanger Park and just one mile from the Trust’s Tewinbury Nature Reserve. These three sites are linked by the river Mimram.
![Archers Green Map](/sites/default/files/styles/scaled_default/public/2022-09/ArchersGreen_map_Final.jpg?itok=anQB4te-)
Importance for wildlife
Covering 8 hectares, Archers Green includes priority habitats, identified in the Herts State of Nature Report. There are lowland meadows, wet woodland, marsh and chalk stream, supporting a wide range of rare plants and animals. This importance is recognised through its designation at a Local Wildlife Site. Chalk streams are internationally important habitats and this is one of the best stretches of the River Mimram.
Seasonal highlights
Spring - Meadow Saxifrage ; Grayling ; Marsh Marigold
Summer – Southern Marsh Orchid ; Dragonflies ; Water-Crowfoot ; Bats ; Yellowhammer
Autumn – Devil’s-bit Scabious ; Bats
Winter - Brown Trout