Railway Lakes

There's something rather appealing about a lake that owes its existence to old railway workings. Railway Lakes, just outside March, is exactly that - a series of flooded gravel pits that have evolved into proper wetland habitat over the decades. You get water, you get birds, you get the kind of place where an afternoon can dissolve without you noticing.

It's an understated spot, which is rather the point. Don't expect manicured paths or visitor centres. What you do get is access to genuinely good birdwatching territory - cormorants, grebes, the occasional rarer migrant depending on season. The walking is straightforward enough, flat ground, though it can get muddy after rain and the exposed stretches mean wind's often a factor.

Walkers and twitchers will get the most from it. Families with young children might find it a bit static after half an hour unless they're seriously into birds. Spring and autumn are when the migration action picks up, making those seasons worth timing a visit around.

If you're staying at Knightsbridge Caravan and Marina Park, just five miles away, Railway Lakes works nicely as a morning outing before heading elsewhere. It's free access and you can spend as long or as little time as you fancy. There's no specific infrastructure to speak of, so come prepared for weather and pack binoculars if you're keen on identification. The Cambridgeshire Fens setting means it slots into a wider walking itinerary rather than being a destination in itself.