Massively parallel contiguity mapping

A method of preparing a sequencing library, comprising:

• (a) contacting a target DNA molecule with a plurality of transposases to insert continuous transposons at a plurality of internal locations in the target DNA molecule to produce a modified target DNA molecule, wherein the continuous transposons each comprise a first flowcell sequence corresponding to a first surface-bound flowcell primer;
• (b) contacting the modified target DNA molecule produced in step (a) with a flowcell to allow hybridization of the first flowcell sequences in the plurality of internally inserted continuous transposons to a plurality of copies of the first surface-bound flowcell primer at co-linear coordinates on the flowcell;
• (c) performing cluster amplification of a plurality of subsequences of the target DNA molecule on the flowcell to produce a plurality of clusters at the co-linear coordinates on the flowcell, wherein each of the plurality of subsequences is adjacent to one of the plurality of internally inserted continuous transposons within the modified target DNA molecule produced in step (a);
• and
• (d) capturing contiguity information by associating sequences of the plurality of subsequences derived from the plurality of clusters at the co-linear coordinates on the flowcell with positions along an axis of the target DNA molecule.