Long Mountain
408mM Marilyn
Long Mountain is a Marilyn, 408m high, and also counts as a HuMP. The Marilyns are hills anywhere in Britain and Ireland with at least 150 metres of prominence, whatever their height.
Welshpool is the nearest station, 2.3 mi (about 3 to 3.5 mi on foot), so the summit is within walking distance of the train. From Welshpool it's about 1.5 hours to the summit, 1 in 11 on average. It is the only station within 10 miles. The Offa's Dyke Path National Trail passes 0.0 mi away.
Stations within 10 miles of Long Mountain, nearest first. Walking distances are estimates from the straight-line distance and the type of ground, not a measured route. Check a map before you set off. Times use Naismith's rule and don't include stops.