Birker Fell, also known as "Birker Moor", is an upland wilderness area in the western portion of the Lake District National Park, in Cumbria, England.
 Rather than being formed of one single high peak, the fell is a broad, undulating area, approximately 6 km square, with numerous crags and prominences scattered across its area.
 The highest point of the fell is at Green Crag (489m, grid reference [ SD200983] ).
 The fell is bordered by the Duddon Valley to the south-east, Ulpha Fell to the south-west, Harter Fell to the north-east, and Eskdale to the north-west.
Keswick ( ) is an English market town and civil parish, historically in Cumberland, and since 1974 in the Borough of Allerdale in Cumbria.
 The town, in the Lake District National Park, just north of Derwentwater, and 4 mi from Bassenthwaite, had a population of 4,821 at the time of the 2011 census.
Muncaster Fell is a fell at the far western edge of the Lake District National Park, in Cumbria, England.
 Muncaster Fell is a long, narrow ridge of land, approximately 1.2 km wide and 6 km long, lying between the River Mite to the north, and River Esk to the south.
 The fell rises from the coast near Ravenglass village to its highest point at Hooker Crag (231 m).
 The ridge then continues to the north-east, dropping gently to its furthest prominence at "Silver Knott" (174 m).
 The fell then falls away rapidly to the village of Eskdale Green at its north-eastern tip.
Blindcrake is a village and civil parish within the Isel Valley, in the Lake District National Park and in the Allerdale district of Cumbria, England.
 According to the 2001 census it had a population of 287, increasing to 348 at the 2011 Census.
 The parish includes Blindcrake village and the hamlets of Redmain, Isel and Sunderland, The whole parish lies within the Lake District National Park and, since 2001, Blindcrake village  is one of 23 designated conservation areas of the National Park Planning Authority.
 This status is largely based on its mediaeval strip field pattern which is described as "undoubtedly the finest example of its type in the Lake District".
 The parish boundary is approximately defined by the Lake District National Park boundary in the north and west, by a line 2 km to the west of the A591 in the east and by the River Derwent in the south.
 It is one of the smallest parishes within the Allerdale district of Cumbria.
 The parish has a website providing local information and lists of events.
Skiddaw is a mountain in the Lake District National Park in England.
 Its 931 m summit is the sixth-highest in England.
 It lies just north of the town of Keswick, Cumbria, and dominates the skyline in this part of the northern lakes.
 It is the simplest of the Lake District mountains of this height to ascend (as there is a well-trodden tourist track from a car park to the north-east of Keswick, near the summit of Latrigg) and, as such, many walking guides recommend it to the occasional walker wishing to climb a mountain.
 This is the first summit of the fell running challenge known as the Bob Graham Round when undertaken in a clockwise direction.
Causey Pike is a fell in the English Lake District.
 It is situated in the Newlands Valley, 5 km south-west of the town of Keswick.
 Even though it has a modest height of 637 metres (2,090 ft) it is one of the most distinctive fells when viewed from the Derwent Water and Keswick area due to its distinguishing summit "knobble" which catches the eye.
 The fell is one of 214 fells described by Alfred Wainwright in his series of "Pictorial Guides to the Lakeland Fells": Causey Pike features in Book Six, "The North Western Fells".
The Windermere Way is a 45-mile circuit of Windermere, a lake in the English Lake District.
 The route is wholly within the Lake District National Park and takes in the summits of Wansfell, Loughrigg Fell and Gummer's How as well as passing through the towns of Ambleside and Windermere.
Slate Fell is a low hill in the North Western part of the English Lake District.
 It lies only about a mile from the busy market town of Cockermouth, and as such is a popular walk for local dog walkers, the amount of climb being only about 80 metres (250 feet).
 A public right of way passes over the summit.
 It is an outlier of the Marilyn Watch Hill, and gives good views of the Lord's Seat group of hills, although it is too low to afford views towards the central Lake District.
 It lies just inside the boundary of the Lake District National Park.
Dent is a small fell on the fringe of the English Lake District near the towns of Cleator Moor and Egremont.
 Sometimes known as Long Barrow, it is traditionally the first fell encountered by hikers following Wainwright’s Coast to Coast Walk.
 It slopes from the westerly point of the Lake District National Park.
Melmerby is a village in Cumbria, England.
 It is a small village with a population of around 200.
 The village is 9 miles to the east of Penrith, a thriving community with immediate access to Junction 40 of the M6 motorway and a main line railway station serving London, Manchester, Edinburgh and Glasgow.
 Melmerby is a quiet backwater with excellent links to other parts of the UK.
 Surrounded by beautiful countryside it sits between the North Pennines with its highest point, Cross Fell to the east and the World Heritage Lake District National Park 10 miles to the west.
 It is relatively quiet because the area is not as popular with tourists as other parts of Cumbria.
 It has ample facilities to support visitors who choose to travel outside the Lake District National Park which can sometimes become congested in high season.
 The River Eden is bridged about 4 mi away at Langwathby, and Long Meg and Her Daughters, the 3,500-year-old stone circle—the second largest in the country—is nearby at Little Salkeld.

Question: What is the height of the distinctive fell in Lake District National Park
Answer: 637 metres