Gravel Cycling
Trossachs Forest Gravel Circuit
The Highland Boundary Fault from the saddle — where lowland farmland meets Highland mountains
Quick facts
- Distance
- 45 km (28 mi)
- Ascent
- 820 m
- Difficulty
- Moderate
- Route type
- Loop
- Archetype
- Forest Circuit
- Region
- Loch Lomond & The Trossachs
- Start point
- Aberfoyle
- Grid ref
- NN 519 009
- Parking
- FK8 3UX
- Midges
- High
- Dogs
- On lead only
Surface breakdown
- Forest track55%
- Tarmac single-track30%
- Double-track15%
About this route
The Trossachs — the 'bristly country' in Gaelic — sit on the Highland Boundary Fault where the geological transition from Lowland Scotland to the Highlands is sudden and dramatic. Aberfoyle is the last Lowland town; 5km north on the Duke's Pass road, you are unambiguously in the Highlands with birch-covered craigs and the Ben A'an summit above. The Queen Elizabeth Forest Park covers the territory between them, and its FLS track network gives access to the best of the transition landscape.
This circuit from Aberfoyle climbs the Duke's Pass (the scenic road through the forest), loops around Loch Drunkie and Loch Achray on the forest roads, and returns via the east shore of Loch Katrine — the reservoir that has supplied Glasgow with water since 1859 and whose shores are managed as a heritage landscape. The Katrine steamship (seasonal) runs tourist cruises that cyclists occasionally time their circuit around — arriving at the pier for a pie and a coffee is achievable.
Highlights
- Duke's Pass summit — the transition from farmland to Highland Scotland is visible in a single sweep of the view
- Loch Drunkie — hidden lochan in the forest that most visitors never find; excellent reflections in still conditions
- Ben A'an from the Loch Achray shore — a perfectly shaped 454m crag that looks twice its height
- Loch Katrine east shore — a heritage landscape of managed shoreline and Victorian planting along the Glasgow waterworks
- Rob Roy's Cave near Aberfoyle — a legendary hideout in the crags above the town, 10 minutes off-route
Key waypoints
- 1. Aberfoyle
- 2. Queen Elizabeth Forest Park
- 3. Loch Drunkie
- 4. Loch Achray
- 5. The Trossachs
- 6. Loch Katrine east shore
- 7. Ben A'an approach
- 8. Aberfoyle return
Cafés & pubs on route
- · Aberfoyle tourist village (multiple)
- · Loch Katrine Steamship café (seasonal)
- · Trossachs Discovery Centre, Aberfoyle
Named climbs
- Duke's Pass (320m)
- Achray Forest climb (280m)
- Loch Katrine head (240m)
Notable descents
- Aberfoyle to Loch Achray descent
- Katrine ridge drop
- Duke's Pass return
Route notes
The Queen Elizabeth Forest Park tracks are a mix of Sustrans Route 7 (signed) and unsigned FLS roads — download OS 1:25k for the full circuit. The Loch Katrine shore road is a private waterworks road but open to cyclists by long-standing convention. No motor vehicles on the Katrine shore — the fastest road in the circuit.
Seasonal conditions
Midges in the forest and at Loch Drunkie June–August are serious. The Duke's Pass is one of Scotland's most spectacular autumn drives — cycling it in October with gold birch on either side is exceptional. The circuit is rideable year-round but the Loch Drunkie forest track is muddy in winter.
Key hazards
- Midges at Loch Drunkie June–August — some of the worst in central Scotland
- Duke's Pass road carries tourist traffic in summer — popular driving route
- The FLS tracks near Loch Drunkie are not well-maintained — some large drainage dips
Water sources on route
- Loch Drunkie shore
- Multiple burns throughout
- Loch Katrine shore (no drinking without filter)
Always filter or treat water from natural sources. Carry at least 1L reserve on remote sections.
OS map sheets
Nearest hill
Ben Lomond
973m · arrochar-trossachs
View hill
Nearest bothy
A' Chuil Bothy
Walk-in: 6 km · glen-coe-lochaber
View bothy
Daylight Today
- Sunrise
- 05:16
- Sunset
- 21:12
- Civil dawn
- 04:28
- Civil dusk
- 22:00
NOAA Solar Calculator · 9 May 2026
Common questions
- Is the Trossachs circuit suitable for children?
- The lower sections (Aberfoyle to Loch Achray via the forest road) are family-friendly. The Duke's Pass section has steeper climbing and shares the road with tourist vehicles. Children under 12 are better served by the dedicated family cycle path in Queen Elizabeth Forest Park (Sustrans Route 7 from Aberfoyle visitor centre).
- Can I take the Loch Katrine steamship during the circuit?
- The SS Sir Walter Scott runs April–October (seasonal, check Loch Katrine website). The boat runs from Trossachs Pier to Stronachlachar on the west shore — you can cycle to Stronachlachar on the west shore track and return by boat, or vice versa, as a scenic addition to the circuit.
- What is the Duke's Pass?
- The Dukes' Road (A821) was built by the Dukes of Montrose in the early 1800s to connect Aberfoyle with the Trossachs Hotel on Loch Achray. It climbs 300m through managed birchwood and was one of Scotland's first tourist roads, predating the modern scenic route industry by 200 years.
- Is there mountain biking in the Trossachs?
- Yes — the Aberfoyle Forest Park has a dedicated trail centre with blue, red, and black-graded MTB routes. The Go Ape activity centre is also in the forest. The gravel circuit described here uses the broader forest road network rather than the designated trail centre routes.