Holzkirchen Seentour (Hackensee → Kirchsee → Kloster Reutberg)
Three lakes and a baroque monastery on a long Voralpen day. Mostly flat with rolling hills. Shorter 10 km variant possible if you skip the Reutberg leg.
Category: S-Bahn + Hiking
Distance: ~20 km (full route) or ~10 km (Hackensee + Kirchsee only)
Difficulty: Long
Bail-out: Multi-leg structure makes mid-route exits possible: bus from Hackensee area back to Holzkirchen, or bus from Reutberg.

Holzkirchen Seentour (Hackensee → Kirchsee → Kloster Reutberg)
Holzkirchen Bahnhof (BRB)
Walk south through old town toward the Hackensee.
Hackensee
First lake. ~5 km in. Swim spot in summer.
Kirchsee
Moor lake — distinct dark water. RECOMMENDED TURNAROUND for shorter variant.
Kloster Reutberg
Full-route end point. Klosterbräustüberl. Bus back to Holzkirchen.