Mountains to Sea and Back Bay Loop
Mountains to Sea and Back Bay Loop
2.9
(18)
22
riders
01:55
40.7km
220m
Road cycling
Embark on the Mountains to Sea and Back Bay Loop, an easy racebike route that guides you through a diverse landscape in Orange County, California. You will cycle 25.3 miles (40.7 km), gaining 726 feet (221 metres) in elevation, with an estimated duration of 1 hour and 54 minutes. Experience the transition from the rugged, oak-filled terrain of Weir Canyon to the expansive coastal wetlands of Upper Newport Bay, offering picturesque views and a refreshing ride.
This accessible route features multiple entry points, making it convenient to start your journey. As you ride the Back Bay Loop section, you will find amenities such as restrooms and water fountains available along the way. The two main sections, the Mountains to Sea Trail and the Back Bay Loop Trail, connect seamlessly, allowing for a continuous and enjoyable cycling experience.
The route takes you through the 50,000-acre Irvine Ranch Land Reserve, a designated Natural Landmark known for its conservation efforts. Along the Upper Newport Bay Nature Preserve and Ecological Reserve, you can observe coastal wetlands and enjoy opportunities for birdwatching, particularly at Castaways Park. This trail offers a unique blend of urban bikeways and significant natural reserves.
Last updated: April 23, 2026
Waypoints
Start point
Train Station
Get Directions
3.77 km
Highlight (Segment) • Cycleway
Tip by
11.2 km
Highlight (Segment) • Trail
Tip by
19.2 km
Highlight • Beach
Tip by
40.7 km
End point
Train Station
Way Types & Surfaces
Way Types
35.3 km
2.68 km
1.25 km
940 m
542 m
Surfaces
23.8 km
16.7 km
121 m
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Elevation
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Weather
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Today
Thursday 7 May
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12°C
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Additional weather tips
Max wind speed: 15.0 km/h
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This route was planned by komoot.
Yes, this route is generally considered easy and suitable for beginners, especially for road cycling. Both the Mountains to Sea Trail and the Back Bay Loop Trail feature mostly paved surfaces and gentle grades, making for a comfortable ride. The Back Bay Loop, in particular, is known for being flat and family-friendly.
The terrain is predominantly paved, consisting of asphalt and some concrete sections. While mostly flat, there are a couple of slight hills, particularly on the Back Bay Loop. The Mountains to Sea Trail also includes some parts that follow concrete water channels. Overall, it's a smooth ride suitable for racebikes.
You'll experience a diverse range of scenery. The Mountains to Sea Trail takes you through parts of the Irvine Ranch Land Reserve, offering views of oak-filled areas, parks, and urban landscapes. The Back Bay Loop Trail provides picturesque views of coastal wetlands, the Upper Newport Bay Nature Preserve, shimmering bay waters, and bluffs of coastal sage scrub, especially at Castaways Park.
Yes, the Back Bay Loop Trail is particularly renowned for its abundant wildlife, especially birds. You can often spot egrets, herons, and ospreys in the Upper Newport Bay Nature Preserve and Ecological Reserve, making it a popular spot for birdwatching.
There are multiple entry points and parking options, especially along the Back Bay Loop. For example, you can find parking near the Peter and Mary Muth Interpretive Center or other access points around the Upper Newport Bay area. Specific parking details can often be found on local city or park websites like newportbeachca.gov.
Generally, there are no permits or entrance fees required to cycle the Mountains to Sea and Back Bay Loop trails themselves. The trails are publicly accessible. However, always check for specific regulations if you plan to visit facilities within the Upper Newport Bay Nature Preserve, though typically access to the trails is free.
While the trails are popular for outdoor activities, specific dog regulations can vary by section and park. The Back Bay Loop is generally considered family-friendly, but it's best to check the specific rules for dogs in the Upper Newport Bay Nature Preserve and along the various segments of the Mountains to Sea Trail. Often, dogs are permitted on leash on paved trails, but may be restricted in sensitive wildlife areas.
The route can be enjoyed year-round due to Southern California's mild climate. Spring and fall offer pleasant temperatures, making them ideal. Summer can be warm, so early mornings or late afternoons are preferable. Winter is also a good time, with cooler weather and fewer crowds.
Yes, particularly along the Back Bay Loop Trail, you will find amenities such as restrooms and water fountains. There are also educational facilities like the Peter and Mary Muth Interpretive Center and the Back Bay Science Center which may offer facilities.
Yes, the route seamlessly connects to several other paths. The Back Bay Loop Trail links directly with the Mountains to Sea Trail. Additionally, the route passes through sections of the California Mission Trail - stage 03 San Juan Capistrano to Mission San Gabriel Arcangel, San Diego Creek Bike Trail, and Peters Canyon Bikeway, among others, allowing for extended rides and exploration.
Given the route's length and exposure, it's advisable to bring plenty of water, sun protection (sunscreen, hat, sunglasses), and snacks. A helmet is essential for safety. While there are some amenities, carrying basic bike repair tools and a first-aid kit is always a good idea. Don't forget binoculars if you're interested in birdwatching!