Marilyns Hills: Britain's 150m Prominence Hill Guide

Key takeaways

• A Marilyn is any hill in Britain or Ireland with at least 150 metres of relative height (prominence), regardless of absolute height.
• The Marilyn list currently stands at roughly 1,557 hills, with Scotland holding about 1,210 of them, and the total drifts as surveys refine col heights.
• Start bagging with a local cluster of five mixed Marilyns, then work outward in rings by driving time to keep the list alive.
• Batching Marilyns by region and checking MWIS summit forecasts beats chasing single peaks, and a full round realistically takes five to ten years.
• Track progress with an app that offers full DoBIH coverage, CSV import, and offline maps, such as Summit Log UK, Hill Lists, or My Summit Log.

The Marilyns hills are the 1,500-plus British and Irish hills with at least 150 metres of relative height, making them the most popular prominence-based list after the Munros. This guide pulls together the qualifying rule, the full regional breakdown, and a concrete first-five-hills starter plan, so you can plan your Marilyn challenge from one page instead of five.

What qualifies a hill as a Marilyn?

A Marilyn is any hill in Britain or Ireland with a relative height (prominence) of at least 150 metres, regardless of its absolute height. The name is a play on Munro: Munros are hills over 3,000 feet, Marilyns are hills with a 150 m drop on all sides.

The 150 metre prominence rule

Prominence measures how far a summit rises above the highest col connecting it to any higher ground. A 200 m hill with a 150 m drop qualifies; a 900 m ridge top with a 30 m drop does not. This is why the list spans everything from coastal headlands to Scottish tops.

Why relative height matters more than absolute height

Prominence identifies genuinely separate hills rather than sub-peaks of a larger massif. For list-tickers, that means every Marilyn is a summit in its own right, not a tick on the way to something bigger.

How the DoBIH defines and maintains the list

The Database of British and Irish Hills maintains the Marilyn classification, publishes the current hill count, and revises the list as survey data refines col heights. It is the source of truth most bagging apps, including Summit Log UK, build their data on.

How many Marilyns are there and where are they?

The Marilyn list currently stands at roughly 1,557 hills, each with a relative height of at least 150 metres on all sides. The count is not fixed: re-surveys and Ordnance Survey map updates occasionally promote or delete hills, so the total drifts by a handful over the years. Most baggers track their total against the latest published list rather than a frozen number.

Distribution by country: Scotland, Wales, England, Ireland, Isle of Man

Scotland dominates the list, which is why many tickers treat the Munros and Marilyns as overlapping projects. The approximate split:

Country	Approx. count
Scotland	~1,210
Ireland (Republic and Northern)	~210
Wales	~157
England	~175
Isle of Man	~2

If you live in England or Wales, there is still a lifetime of local bagging before you ever need a ferry north.

How is the Marilyn list organised by region?

The standard regional sections used by baggers

The full Marilyn list, compiled by Alan Dawson in The Relative Hills of Britain, is traditionally split into broad geographic areas: Scotland (often further split into Highlands, Central, and Southern), Northern England, Wales and the Borders, Ireland, and the islands, including the Isle of Man and the Channel Islands. Most tickers track progress against these sections rather than the raw list.

Mapping regions to realistic weekend trips

Regions map loosely onto driving distance. Southern Scotland and Northern England suit a weekend from most of England; Wales works as a long weekend; Ireland usually needs dedicated trips. Islands are the exception: they cost ferry time, so baggers plan them as standalone holidays rather than weekend batches.

Where each region's density makes batching easy or hard

Density varies enormously. The Central Lowlands of Scotland pack many Marilyns close together, so a single day can tick several. Highland and Irish Marilyns are spread out, often one summit per walk, so those regions dominate the time budget even when the hill count looks even.

Which Marilyns should you bag first?

Start where you live: the local-density advantage

Your first Marilyns should be the ones near home, because proximity is what keeps a list alive. A Marilyn within an hour's drive gets ticked on a free Tuesday; one six hours away waits for a planned trip that may never come. Most regions of Britain and Ireland hold dozens of Marilyns, so almost every bagger starts with a local cluster, and those early ticks build the logging habit and the ascent records that the rest of the list depends on. Work outward in rings: everything under an hour first, then everything under two, and only then start stitching distant hills into multi-summit trips.

This also means your early summits are ones you can revisit in poor weather without wasted fuel, and you learn how your own logging and planning setup copes with real conditions before you commit to far-flung weekends. The honest drawback: starting local delays the famous hills, and if you tick only easy local tops you may reach fifty Marilyns without ever having tackled a proper scramble route. Accept that trade-off deliberately rather than by accident.

A first-five plan for each major region

Pick five nearby Marilyns of mixed character: one coastal, one moorland, one woodland or park hill, one with a short steep pull, and one you can chain with another on the same walk. That mix tests every skill the full list will demand.

Balancing easy wins against iconic summits

Once the local cluster is moving, schedule one iconic Marilyn per quarter. Ben Nevis, Snowdon, Carrauntoohil, and Scafell Pike are all Marilyns, and bagging them early keeps motivation high while the local ticks accumulate quietly underneath.

How do you plan a route to completing all the Marilyns?

Batching by region vs chasing weather windows

Most baggers who finish a round batch by region rather than driving single-peak distances. Grouping, say, the Southern Uplands or the Lake District fells into one trip cuts travel time per ascent and lets you link nearby Marilyns over a weekend. The trade-off is flexibility: a fixed regional plan can waste a good forecast, so many baggers hold a shortlist of target areas and pick whichever region the weather favours that week.

Using MWIS and forecast tools to plan trips

The Mountain Weather Information Service publishes forecasts for Scotland, Northern England, and Wales, including cloud level, freezing level, and summit wind speed, which matter more than valley temperatures when your objective is a 150m prominence top (https://www.mwis.org.uk). Checking MWIS alongside Met Office forecasts before committing to a drive is standard practice for anyone bagging exposed summit tops in winter or shoulder season.

Tracking progress: logs, CSVs, and apps

A full round is 1,500+ ascents of management, so keep a permanent log from day one. Export your existing records as a CSV, import them into a logging app, and reconcile against the full list so completed, planned, and unclimbed hills stay current. Summit Log UK handles CSV import, auto summit detection, and per-list progress; Hill Lists and My Summit Log serve the same tracking job if you prefer alternatives.

Which tools and apps help with Marilyn bagging?

What to look for in a bagging app

Your app needs full DoBIH coverage, CSV import for years of existing logs, and offline maps for the hills where signal dies. Prominence-based filtering matters too, because Marilyns sit inside bigger lists and you will want to tick them wherever they appear. Weather access for summit windows is a genuine planning tool, not a nice-to-have.

How Summit Log UK handles Marilyns and how it excels.

Summit Log UK auto-detects summits across hill lists including Marilyns, logs ascents permanently, imports your CSV history, and supports GPX routes, photos, and voice notes per bag. Trip planning and personalised statistics cover the long grind. Where it excels is its multi platform capability is iOS, Android and web and its ability to log on any device and have it open on multiple devices simultaneously. it does not replace a dedicated Marilyn-region breakdown for building a county-by-county plan but it does give you a wide range of options.

Comparing the main options

Hill Bagging, BaggedIt - Hill Tracker, Trailwise: Fell & Peak Bagging, Hill Lists, and My Summit Log all serve list-tickers. Judge each against the same criteria: DoBIH coverage, import, offline use, and how it fits your Marilyn strategy rather than replacing it.

What are the hardest and most notable Marilyns?

Sea cliff and island Marilyns

Coastal Marilyns carry the list's most serious terrain: Slieve League's sea cliffs in Donegal, the Old Man of Stoer and Cape Wrath's Clo Mor cliffs in northwest Scotland, and island outliers like Barra's Heaval or Fair Isle's Ward Hill. Several require boat access or tide-dependent crossings, so pair them with a planning window checked against MWIS forecasts and ferry timetables. Log conditions, route notes and photos per ascent so a return visit for a better line is easy to justify.

Long walk-ins and remoteness outliers

The Kintail and Affric Marilyns hide behind hours of stalking-track walking, while Sutherland's Arkle, Foinaven and Ben Hope demand full days from single-track roads. Ruadh-stac Mor and the Fannaichs sit in terrain where navigation matters more than fitness. Build these as multi-day trips rather than singles.

Scramble routes on Marilyns

A handful of Marilyns double as classic scrambles: the Dubhs Ridge on Skye's Sgurr Dubh, Sharp Edge on Blencathra, and Striding Edge on Helvellyn. Grade them honestly against your experience, and record which line you took. Most logging apps, including Hill Bagging, let you attach GPX tracks and notes to each summit entry (App Store listings for hill-bagging apps), which is worth doing before you forget the descent route.

How long does it take to complete the Marilyns?

Casual weekend pace vs round-attempt pace

At one Marilyn a month, you are looking at roughly 13 years for the full 1,500-plus list. At one a week, that drops to about 30 years. A round-attempt pace of two or three per weekend, sustained through spring and autumn, brings a completion inside five to seven years. The maths is brutal but simple: the list length rewards consistency far more than fitness.

What completionists report

Baggers who finish report the same pattern: the first third goes quickly on accessible southern Marilyns, then the Scottish islands, far northwest, and Irish entries slow everything down. Ferry timetables and single-track roads become the limiting factor, not legs. Most finishers describe the last 50 as a deliberate scheduling exercise, grouping remote Grahams-adjacent Marilyns into multi-day trips. Plan for a decade, and treat anything faster as a bonus.

FAQ

Is a Marilyn the same as a Wainwright or a Munro?

No. Munros are Scottish hills over 3,000 feet by absolute height; Wainwrights are a fixed 214-hill catalogue of the Lake District. Marilyns are defined purely by 150 metres of prominence anywhere in Britain or Ireland. The lists overlap: Ben Nevis and Scafell Pike are both Marilyns, but many lowland Marilyns appear on neither other list.

How do I log a Marilyn I climbed before I started keeping records?

Enter the hill and the ascent date manually, even if the date is approximate. Most logging apps, including Summit Log UK, accept manual entries with a month or year rather than an exact timestamp. A rough date preserves the ordering of your history, the ascent still counts against the list, and guessing a precise day you cannot verify adds nothing.

What counts as the summit of a Marilyn with multiple tops?

The qualifying summit is the highest point of the hill itself, not the point with the most prominence on the broader massif. If two tops both carry 150 metres of drop, they are separate Marilyns and each needs its own tick. DoBIH data identifies which top is the listed summit, so check the database entry rather than assuming the obvious path high point.

Can I import my existing spreadsheet of ascents into a bagging app?

Yes, if the app supports CSV import, which Summit Log UK, Hill Lists, and My Summit Log all do. Export your spreadsheet with columns for hill name and ascent date, match them to the DoBIH hill list during import, and reconcile the result against the full Marilyn list. Summit Log UK prompts you for unmatched hills with what it thinks are those hill for you to pick from, so no need to have to fix by hand trying to match unmatched hills by hand once.